Withdrawn by the publisher.

Affected: CleanStart: kube-metrics-adapter

Multiple security vulnerabilities affect the kube-metrics-adapter package. Echo is a Go web framework. See references for individual vulnerability details.

The package `github.com/gomarkdown/markdown` is a Go library for parsing Markdown text and rendering as HTML. Processing a malformed input containing a < character that is not followed by a > character anywhere in the remaining text with a SmartypantsRenderer will lead to Out of Bounds read or a panic. This vulnerability is fixed with commit 759bbc3e32073c3bc4e25969c132fc520eda2778.

Affected: Go: github.com/gomarkdown/markdown

### Summary

Processing a malformed input containing a `<` character that is not followed by a `>` character anywhere in the remaining text with a SmartypantsRenderer will lead to Out of Bounds read or a panic.

### Details

The `smartLeftAngle()` function in `html/smartypants.go:367-376` performs an out-of-bounds slice operation when processing a `<` character that is not followed by a `>` character anywhere in the remaining text. https://github.com/gomarkdown/markdown/blob/37c66b85d6ab025ba67a73ba03b7f3ef55859cca/html/smartypants.go#L367-L376 If the length of the slice is lower than its capacity, this leads to an extra byte of data read. If the length equals the capacity, this leads to a panic.

### PoC ```golang package main

import ( "bytes" "fmt"

"github.com/gomarkdown/markdown/html" )

func main() { src := []byte("<a")

fmt.Printf("Input: %q (len=%d, cap=%d)\n", src, len(src), cap(src))

var buf bytes.Buffer sp := html.NewSmartypantsRenderer(html.Smartypants) sp.Process(&buf, src) // panics: slice bounds out of range

fmt.Printf("Output: %q\n", buf.String()) } ```

### Impact This vulnerability will lead to a Denial of Service / panic on the processing service.

-- The Datadog Security Team

grafana/tempo: Tempo: Denial of Service via large queries net/url: Incorrect parsing of IPv6 host literals in net/url crypto/x509: Incorrect enforcement of email constraints in crypto/x509 github.com/nats-io/nats-server: NATS-Server: Denial of Service via malformed WebSockets frame github.com/nats-io/nats-server: NATS-Server: Denial of Service via leafnode compression crypto/x509: crypto/tls: golang: Go: Denial of Service vulnerability in certificate chain building crypto/x509: golang: Go crypto/x509: Denial of Service via inefficient certificate chain validation golang: internal/syscall/unix: Root.Chmod can follow symlinks out of the root crypto/tls: golang: Go crypto/tls: Denial of Service via multiple TLS 1.3 key update messages github.com/buger/jsonparser: github.com/buger/jsonparser: Denial of Service via malformed JSON input github.com/jackc/pgproto3/v2: github.com/jackc/pgproto3/v2: Denial of Service via malicious PostgreSQL server google.golang.org/grpc/grpc-go: google.golang.org/grpc/authz: gRPC-Go: Authorization bypass due to improper HTTP/2 path validation nats-server: NATS-Server: Session and message hijacking via MQTT Client ID malfeasance nats-server: github.com/nats-io/nats-server: NATS-Server: Information disclosure of MQTT passwords through monitoring endpoints nats-server: github.com/nats-io/nats-server: NATS-Server: Access control bypass via unapplied ACLs in MQTT namespace nats-server: github.com/nats-io/nats-server: NATS-Server: Denial of Service via mal…

Affected: Ubuntu:24.04:LTS: golang-github-gomarkdown-markdown, Ubuntu:25.10: golang-github-gomarkdown-markdown, Ubuntu:26.04:LTS: golang-github-gomarkdown-markdown

The package `github.com/gomarkdown/markdown` is a Go library for parsing Markdown text and rendering as HTML. Processing a malformed input containing a < character that is not followed by a > character anywhere in the remaining text with a SmartypantsRenderer will lead to Out of Bounds read or a panic. This vulnerability is fixed with commit 759bbc3e32073c3bc4e25969c132fc520eda2778.