HomeCVE Intelligence › CVE-2026-58436
CVSS 7.5 HIGH Vulnerability

CVE-2026-58436: Gitea: ParseAcceptLanguage quadratic-time DoS via Locale middleware on unauthenticated re…

Summary The Locale middleware that runs in front of every unauthenticated request calls golang.org/x/text/language.ParseAcceptLanguage on the raw Accept-Language header without imposing a size or shape filter. The under…

7.5CVSS Score
HIGHSeverity
NOCISA KEV
VulnerabilityImpact Type

📋 Vulnerability Details

CVE IDCVE-2026-58436
Vendorgo
Affected Productcode.gitea.io/gitea
Vulnerability TypeVulnerability
CVSS Score7.5 (HIGH)
Actively Exploited❌ No known exploitation
Patch StatusSee Vendor Advisory →
Reported ByCYBERDUDEBIVASH SENTINEL APEX Intelligence (via github_advisories)

🔬 Technical Analysis

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Summary The Locale middleware that runs in front of every unauthenticated request

calls golang.org/x/text/language.ParseAcceptLanguage on the raw Accept-Language header without imposing a size or shape filter. The underlying parser has quadratic-time behaviour on long lists of malformed language tags. The CVE-2022-32149 guard that golang.org/x/text added in v0.3.8 caps the number of - characters in the input at 1000, but it does not cap _ characters even though the parser's internal scanner aliases _ to - before parsing. A single unauthenticated GET request with an Accept-Language header built out of _ separators burns ~2 seconds of server CPU on the host running Gitea; ten concurrent attackers saturate a ten-core box for the duration of the attack while consuming ~1 Mi

🎯 Known Indicators of Compromise

{"type":"domain","value":"golang.org","confidence_score":0.75,"first_seen":"2026-07-21","source_count":1}

📚 Advisory References

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