CVE-2026-77643 (GCVE-0-2026-77643)

Vulnerability from cvelistv5 – Published: 2026-08-20 21:23 – Updated: 2026-08-28 18:08
VLAI
Summary
A cross-site scripting vulnerability in queryparser/termgenerator_internal.cc in Xapian xapian-core before 2.1.0 and before 1.4.32 exists due to incomplete HTML escaping by Xapian::MSet::snippet(). NOTE: this issue exists because of a missed corner case of CVE-2018-0499.
Severity
4.4 (Medium)
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:L/I:L/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-28 18:08 UTC
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting')
Assigner
References
Impacted products
Vendor Product Version
Xapian xapian-core Affected: 2.0.0 , < 2.1.0 (semver)
Affected: 0 , < 1.4.32 (semver)
    cpe:2.3:a:xapian:xapian-core:*:*:*:*:*:*:*:*
    cpe:2.3:a:xapian:xapian-core:*:*:*:*:*:*:*:*
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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

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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.



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.