CVE-2026-26275 httpsig-hyper has Improper Digest Verification that May Allow Message Integrity Bypass
Attackers can bypass HTTP message integrity checks due to flawed digest verification logic in the httpsig-hyper library.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-26275?
CVE-2026-26275 is a high-severity vulnerability in junkurihara httpsig-rs, published on 19 Feb 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
httpsig-hyper is a hyper extension for http message signatures. An issue was discovered in `httpsig-hyper` prior to version 0.0.23 where Digest header verification could incorrectly succeed due to misuse of Rust's `matches!` macro. Specifically, the comparison `if matches!(digest, _expected_digest)` treated `_expected_digest` as a pattern binding rather than a value comparison, resulting in unconditional success of the match expression. As a consequence, digest verification could incorrectly return success even when the computed digest did not match the expected value. Applications relying on Digest verification as part of HTTP message signature validation may therefore fail to detect message body modification. The severity depends on how the library is integrated and whether additional signature validation layers are enforced. This issue has been fixed in `httpsig-hyper` 0.0.23. The fix replaces the incorrect `matches!` usage with proper value comparison and additionally introduces constant-time comparison for digest verification as defense-in-depth. Regression tests have also been added to prevent reintroduction of this issue. Users are strongly advised to upgrade to the patched version. There is no reliable workaround without upgrading. Users who cannot immediately upgrade should avoid relying solely on Digest verification for message integrity and ensure that full HTTP message signature verification is enforced at the application layer.
Which versions are affected by CVE-2026-26275?
2 open source packages ship an affected version, including httpsig-hyper. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
httpsig-hyper crates.io | All versions | 0.0.23 |
httpsig-hyper crates.io | All versions | 0.0.23 |
Products include Junkurihara Httpsig-Hyper.
How do I fix CVE-2026-26275?
Upgrade httpsig-hyper to 0.0.23 or later.
Is CVE-2026-26275 being exploited?
There is no known exploitation of CVE-2026-26275 in the wild and no public exploit code.
Sources
Also known as GHSA-7v42-g35v-xrch.