Is CVE-2026-38637 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-38637 being exploited in the wild.

How severe is CVE-2026-38637?

Informational severity, with a CVSS score of 4, published 25 June 2026.

Which products and versions are affected?

Redox OS Relibc commit 61f42d6b93adc552a9e8b6f207fca907e8ca8be2.

Is there a fix for CVE-2026-38637?

A patch was published on 2026-02-10: Merge request !987 submitted to handle invalid pshared values. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-38637 attacked?

It is attacked with local access, in a software library.

Am I affected by CVE-2026-38637?

Check whether you run Redox OS Relibc at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-38637: Redox OS relibc Denial of Service in pthread_rwlockattr_setpshared

CVE-2026-38637 · Severity: info · CVSS 4 · Published 2026-06-25

A vulnerability exists in relibc, a core C library used by the Redox operating system. An attacker can cause a program to crash by providing unexpected input to a specific system function. This results in a denial-of-service condition where the affected application stops functioning, potentially impacting system stability or service availability.

Technologies: Redox OS Relibc. Vendors: Redox OS.

Quick answers

Is CVE-2026-38637 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-38637 being exploited in the wild.
How severe is CVE-2026-38637?: Informational severity, with a CVSS score of 4, published 25 June 2026.
Which products and versions are affected?: Redox OS Relibc commit 61f42d6b93adc552a9e8b6f207fca907e8ca8be2.
Is there a fix for CVE-2026-38637?: A patch was published on 2026-02-10: Merge request !987 submitted to handle invalid pshared values. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-38637 attacked?: It is attacked with local access, in a software library.
Am I affected by CVE-2026-38637?: Check whether you run Redox OS Relibc at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

A reachable 'expect' panic exists in the pthread_rwlockattr_setpshared() function within relibc (specifically in src/header/pthread/rwlock.rs). The root cause is the use of .expect() on a Result/Option returned by Pshared::from_raw() when an invalid pshared value (neither PTHREAD_PROCESS_PRIVATE nor PTHREAD_PROCESS_SHARED) is provided. A local attacker can trigger this panic by executing a program that passes an unsupported integer to the function, leading to an immediate process crash (SIGILL/Invalid Opcode). A fix has been proposed in merge request !987 to return EINVAL instead of panicking.

Affected products

Redox OS relibc commit 61f42d6b93adc552a9e8b6f207fca907e8ca8be2

Timeline

2026-02-10: patched: Merge request !987 submitted to handle invalid pshared values.
2026-06-25: disclosed: CVE-2026-38637 published.

References

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