# Improper Digest Verification in httpsig-hyper May Allow Message Integrity Bypass

Advisory record · `GHSA-7v42-g35v-xrch`

- **Identifiers:** `GHSA-7v42-g35v-xrch` · `CVE-2026-26275`
- **State:** Confirmed
- **Severity:** CVSS 7.5 High
- **Critical:** No
- **Weakness (CWE):** [CWE-354](https://cwe.mitre.org/data/definitions/354.html) · [CWE-697](https://cwe.mitre.org/data/definitions/697.html)
- **Tags:** [CWE-354](https://agentprime.io/advisories/tag/cwe-354.md) · [CWE-697](https://agentprime.io/advisories/tag/cwe-697.md)
- **Published:** 17 Feb 2026
- **Updated:** 20 Feb 2026
- **Reviewed by a person:** No

Published by the GitHub Advisory Database at 17 Feb 2026, 21:29 UTC. agentprime has not analysed this yet, so whether it affects any app is not known.

## Affected packages

- `httpsig-hyper` (crates.io): affected `<0.0.23`; fixed in `0.0.23`

## Not analysed yet

We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.

## Severity and exploitation

- 7.5 High, CVSS 3.1: `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N`, from CNA (GitHub_M)

- **CISA KEV:** Not listed.
- **EPSS:** 0.0018, the 8th percentile, on 5 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

## Timeline

- 31 Oct 2026, 15:19 UTC: First seen by agentprime
- 31 Oct 2026, 15:19 UTC: [Confirmed by OSV](https://osv.dev/vulnerability/GHSA-7v42-g35v-xrch)

## Sources

- [GitHub Advisory Database: GHSA-7v42-g35v-xrch](https://github.com/advisories/GHSA-7v42-g35v-xrch)
- [OSV: GHSA-7v42-g35v-xrch](https://osv.dev/vulnerability/GHSA-7v42-g35v-xrch)
- <https://github.com/junkurihara/httpsig-rs/security/advisories/GHSA-7v42-g35v-xrch>
- <https://nvd.nist.gov/vuln/detail/CVE-2026-26275>
- <https://github.com/junkurihara/httpsig-rs/pull/14>
- <https://github.com/junkurihara/httpsig-rs/pull/15>
- <https://github.com/junkurihara/httpsig-rs/commit/5533f596c650377e02f4aa9e3eb8dba591b87370>
- <https://github.com/junkurihara/httpsig-rs/commit/65cbd19b395180a4bba09a89746c4b14ccb8d297>
- <https://github.com/junkurihara/httpsig-rs>

Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code.

## Check whether this affects you

A Match means an installed version is in the affected range above. Most don’t affect the app; agentprime hasn’t analysed this one yet.

- With the agentprime MCP server (<https://api.agentprime.io/mcp>), ask your agent to check the project: `check_lockfile` sends a lockfile, `check_packages` a list of installed packages, and both return the Matches and the upgrades that clear them. `get_advisory` returns this record. Setup: <https://agentprime.io/mcp.md>
- In a browser: <https://agentprime.io/check/> reads your lockfile in the browser, never uploading it.
- Whether it touches your code, with file and line: the Claude Code plugin, <https://agentprime.io/plugin.md>
- As JSON: <https://api.agentprime.io/v1/advisories/GHSA-7v42-g35v-xrch>, or `POST https://api.agentprime.io/v1/match` with your packages (<https://agentprime.io/api.md>)

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The web page: <https://agentprime.io/advisories/GHSA-7v42-g35v-xrch/>. Everything for agents: <https://agentprime.io/llms.txt>.