CVE-2026-21899 (GCVE-0-2026-21899)
Vulnerability from cvelistv5 – Published: 2026-01-10 00:11 – Updated: 2026-01-12 20:23
VLAI
EPSS
VEX
Title
CryptoLib has an out-of-bounds read and crash vulnerability when decoding an empty Base64url string
Summary
CryptoLib provides a software-only solution using the CCSDS Space Data Link Security Protocol - Extended Procedures (SDLS-EP) to secure communications between a spacecraft running the core Flight System (cFS) and a ground station. Prior to version 1.4.3, in base64urlDecode, padding-stripping dereferences input[inputLen - 1] before checking that inputLen > 0 or that input != NULL. For inputLen == 0, this becomes an OOB read at input[-1], potentially crashing the process. If input == NULL and inputLen == 0, it dereferences NULL - 1. This issue has been patched in version 1.4.3.
Severity
4.7 (Medium)
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-01-12 20:22 UTC
CWE
- CWE-125 - Out-of-bounds Read
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/nasa/CryptoLib/security/adviso… | x_refsource_CONFIRM |
| https://github.com/nasa/CryptoLib/releases/tag/v1.4.3 | x_refsource_MISC |
{
"containers": {
"adp": [
{
"metrics": [
{
"other": {
"content": {
"id": "CVE-2026-21899",
"options": [
{
"Exploitation": "none"
},
{
"Automatable": "no"
},
{
"Technical Impact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-01-12T20:22:54.955002Z",
"version": "2.0.3"
},
"type": "ssvc"
}
}
],
"providerMetadata": {
"dateUpdated": "2026-01-12T20:23:08.304Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"title": "CISA ADP Vulnrichment"
}
],
"cna": {
"affected": [
{
"product": "CryptoLib",
"vendor": "nasa",
"versions": [
{
"status": "affected",
"version": "\u003c 1.4.3"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "CryptoLib provides a software-only solution using the CCSDS Space Data Link Security Protocol - Extended Procedures (SDLS-EP) to secure communications between a spacecraft running the core Flight System (cFS) and a ground station. Prior to version 1.4.3, in base64urlDecode, padding-stripping dereferences input[inputLen - 1] before checking that inputLen \u003e 0 or that input != NULL. For inputLen == 0, this becomes an OOB read at input[-1], potentially crashing the process. If input == NULL and inputLen == 0, it dereferences NULL - 1. This issue has been patched in version 1.4.3."
}
],
"metrics": [
{
"cvssV3_1": {
"attackComplexity": "LOW",
"attackVector": "NETWORK",
"availabilityImpact": "LOW",
"baseScore": 4.7,
"baseSeverity": "MEDIUM",
"confidentialityImpact": "LOW",
"integrityImpact": "LOW",
"privilegesRequired": "HIGH",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:L",
"version": "3.1"
}
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-125",
"description": "CWE-125: Out-of-bounds Read",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-01-10T00:11:18.877Z",
"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
"shortName": "GitHub_M"
},
"references": [
{
"name": "https://github.com/nasa/CryptoLib/security/advisories/GHSA-wc29-5hw7-mpj8",
"tags": [
"x_refsource_CONFIRM"
],
"url": "https://github.com/nasa/CryptoLib/security/advisories/GHSA-wc29-5hw7-mpj8"
},
{
"name": "https://github.com/nasa/CryptoLib/releases/tag/v1.4.3",
"tags": [
"x_refsource_MISC"
],
"url": "https://github.com/nasa/CryptoLib/releases/tag/v1.4.3"
}
],
"source": {
"advisory": "GHSA-wc29-5hw7-mpj8",
"discovery": "UNKNOWN"
},
"title": "CryptoLib has an out-of-bounds read and crash vulnerability when decoding an empty Base64url string"
}
},
"cveMetadata": {
"assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
"assignerShortName": "GitHub_M",
"cveId": "CVE-2026-21899",
"datePublished": "2026-01-10T00:11:18.877Z",
"dateReserved": "2026-01-05T17:24:36.931Z",
"dateUpdated": "2026-01-12T20:23:08.304Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"vulnerability-lookup:meta": {
"epss": {
"cve": "CVE-2026-21899",
"date": "2026-10-01",
"epss": "0.0035",
"percentile": "0.26232"
},
"nvd": {
"cve": {
"affected": [
{
"affectedData": [
{
"product": "CryptoLib",
"vendor": "nasa",
"versions": [
{
"status": "affected",
"version": "\u003c 1.4.3"
}
]
}
],
"source": "security-advisories@github.com"
}
],
"configurations": [
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:a:nasa:cryptolib:*:*:*:*:*:*:*:*",
"matchCriteriaId": "AE1BE91E-2901-42AF-BC66-762CFA7A2582",
"versionEndExcluding": "1.4.3",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
],
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "CryptoLib provides a software-only solution using the CCSDS Space Data Link Security Protocol - Extended Procedures (SDLS-EP) to secure communications between a spacecraft running the core Flight System (cFS) and a ground station. Prior to version 1.4.3, in base64urlDecode, padding-stripping dereferences input[inputLen - 1] before checking that inputLen \u003e 0 or that input != NULL. For inputLen == 0, this becomes an OOB read at input[-1], potentially crashing the process. If input == NULL and inputLen == 0, it dereferences NULL - 1. This issue has been patched in version 1.4.3."
},
{
"lang": "es",
"value": "CryptoLib proporciona una soluci\u00f3n \u00fanicamente de software utilizando el Protocolo de Seguridad de Enlace de Datos Espaciales CCSDS - Procedimientos Extendidos (SDLS-EP) para asegurar las comunicaciones entre una nave espacial que ejecuta el Sistema de Vuelo central (cFS) y una estaci\u00f3n terrestre. Antes de la versi\u00f3n 1.4.3, en base64urlDecode, la eliminaci\u00f3n de relleno desreferencia input[inputLen - 1] antes de verificar que inputLen \u0026gt; 0 o que input != NULL. Para inputLen == 0, esto se convierte en una lectura fuera de l\u00edmites (OOB read) en input[-1], lo que podr\u00eda bloquear el proceso. Si input == NULL e inputLen == 0, desreferencia NULL - 1. Este problema ha sido parcheado en la versi\u00f3n 1.4.3."
}
],
"id": "CVE-2026-21899",
"lastModified": "2026-06-17T10:19:06.903",
"metrics": {
"cvssMetricV31": [
{
"cvssData": {
"attackComplexity": "LOW",
"attackVector": "NETWORK",
"availabilityImpact": "LOW",
"baseScore": 4.7,
"baseSeverity": "MEDIUM",
"confidentialityImpact": "LOW",
"integrityImpact": "LOW",
"privilegesRequired": "HIGH",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:L",
"version": "3.1"
},
"exploitabilityScore": 1.2,
"impactScore": 3.4,
"source": "security-advisories@github.com",
"type": "Secondary"
},
{
"cvssData": {
"attackComplexity": "LOW",
"attackVector": "NETWORK",
"availabilityImpact": "HIGH",
"baseScore": 4.9,
"baseSeverity": "MEDIUM",
"confidentialityImpact": "NONE",
"integrityImpact": "NONE",
"privilegesRequired": "HIGH",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H",
"version": "3.1"
},
"exploitabilityScore": 1.2,
"impactScore": 3.6,
"source": "nvd@nist.gov",
"type": "Primary"
}
],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2026-21899",
"options": [
{
"exploitation": "none"
},
{
"automatable": "no"
},
{
"technicalImpact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-01-12T20:22:54.955002Z",
"version": "2.0.3"
}
}
]
},
"published": "2026-01-10T01:16:18.113",
"references": [
{
"source": "security-advisories@github.com",
"tags": [
"Release Notes"
],
"url": "https://github.com/nasa/CryptoLib/releases/tag/v1.4.3"
},
{
"source": "security-advisories@github.com",
"tags": [
"Exploit",
"Vendor Advisory"
],
"url": "https://github.com/nasa/CryptoLib/security/advisories/GHSA-wc29-5hw7-mpj8"
}
],
"sourceIdentifier": "security-advisories@github.com",
"vulnStatus": "Analyzed",
"weaknesses": [
{
"description": [
{
"lang": "en",
"value": "CWE-125"
}
],
"source": "security-advisories@github.com",
"type": "Secondary"
}
]
}
},
"vulnrichment": {
"containers": {
"adp": [
{
"metrics": [
{
"other": {
"content": {
"id": "CVE-2026-21899",
"options": [
{
"Exploitation": "none"
},
{
"Automatable": "no"
},
{
"Technical Impact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-01-12T20:22:54.955002Z",
"version": "2.0.3"
},
"type": "ssvc"
}
}
],
"providerMetadata": {
"dateUpdated": "2026-01-12T20:22:58.538Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"title": "CISA ADP Vulnrichment"
}
],
"cna": {
"affected": [
{
"product": "CryptoLib",
"vendor": "nasa",
"versions": [
{
"status": "affected",
"version": "\u003c 1.4.3"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "CryptoLib provides a software-only solution using the CCSDS Space Data Link Security Protocol - Extended Procedures (SDLS-EP) to secure communications between a spacecraft running the core Flight System (cFS) and a ground station. Prior to version 1.4.3, in base64urlDecode, padding-stripping dereferences input[inputLen - 1] before checking that inputLen \u003e 0 or that input != NULL. For inputLen == 0, this becomes an OOB read at input[-1], potentially crashing the process. If input == NULL and inputLen == 0, it dereferences NULL - 1. This issue has been patched in version 1.4.3."
}
],
"metrics": [
{
"cvssV3_1": {
"attackComplexity": "LOW",
"attackVector": "NETWORK",
"availabilityImpact": "LOW",
"baseScore": 4.7,
"baseSeverity": "MEDIUM",
"confidentialityImpact": "LOW",
"integrityImpact": "LOW",
"privilegesRequired": "HIGH",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:L",
"version": "3.1"
}
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-125",
"description": "CWE-125: Out-of-bounds Read",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-01-10T00:11:18.877Z",
"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
"shortName": "GitHub_M"
},
"references": [
{
"name": "https://github.com/nasa/CryptoLib/security/advisories/GHSA-wc29-5hw7-mpj8",
"tags": [
"x_refsource_CONFIRM"
],
"url": "https://github.com/nasa/CryptoLib/security/advisories/GHSA-wc29-5hw7-mpj8"
},
{
"name": "https://github.com/nasa/CryptoLib/releases/tag/v1.4.3",
"tags": [
"x_refsource_MISC"
],
"url": "https://github.com/nasa/CryptoLib/releases/tag/v1.4.3"
}
],
"source": {
"advisory": "GHSA-wc29-5hw7-mpj8",
"discovery": "UNKNOWN"
},
"title": "CryptoLib has an out-of-bounds read and crash vulnerability when decoding an empty Base64url string"
}
},
"cveMetadata": {
"assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
"assignerShortName": "GitHub_M",
"cveId": "CVE-2026-21899",
"datePublished": "2026-01-10T00:11:18.877Z",
"dateReserved": "2026-01-05T17:24:36.931Z",
"dateUpdated": "2026-01-12T20:23:08.304Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2"
}
}
}
Loading…
Loading…
Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
Loading…
Loading…
The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
Loading…
Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.
Loading…