What’s Vulnerable › Vulnerabilities

CVE-2021-38561: Out-of-bounds read in golang.org/x/text/language

• Severity: high (CVSS 7.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.5% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2022-12-26 · updated 2026-06-17
• Weakness: CWE-125

Description

golang.org/x/text/language in golang.org/x/text before 0.3.7 can panic with an out-of-bounds read during BCP 47 language tag parsing. Index calculation is mishandled. If parsing untrusted user input, this can be used as a vector for a denial-of-service attack.

Affected products

• golang.org/x/text/language: before 0.3.7 — fixed in 0.3.7
• Golang.Org/X/Text: before 0.3.7 — fixed in 0.3.7

How to fix

Upgrade to a fixed version: golang.org/x/text/language 0.3.7; Golang.Org/X/Text 0.3.7. Check the vendor advisory for mitigations.

References

• https://deps.dev/advisory/OSV/GO-2021-0113
• https://go.googlesource.com/text/+/383b2e75a7a4198c42f8f87833eefb772868a56f
• https://groups.google.com/g/golang-announce
• https://pkg.go.dev/golang.org/x/text/language
• https://deps.dev/advisory/OSV/GO-2021-0113
• https://go.googlesource.com/text/+/383b2e75a7a4198c42f8f87833eefb772868a56f
• https://groups.google.com/g/golang-announce
• https://pkg.go.dev/golang.org/x/text/language

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