# openssl_encrypt versions before 1.4.9 fail to properly validate key derivation function costs in crafted files, allowing attackers to trigger unbounded memory and CPU exhaustion during pre-authenti...

Advisory record · `GHSA-phmr-p567-q5g6`

- **Identifiers:** `GHSA-phmr-p567-q5g6` · `CVE-2026-81699` · `PYSEC-2026-3961`
- **State:** Confirmed
- **Severity:** CVSS 8.7 High
- **Critical:** No
- **Weakness (CWE):** [CWE-770](https://cwe.mitre.org/data/definitions/770.html)
- **Tags:** [Denial of service](https://agentprime.io/advisories/tag/dos.md)
- **Published:** 27 Aug 2026
- **Updated:** 10 Sept 2026
- **Reviewed by a person:** No

Published by the GitHub Advisory Database at 27 Aug 2026, 17:21 UTC. agentprime has not analysed this yet, so whether it affects any app is not known.

## Affected packages

- `openssl-encrypt` (PyPI): affected `<1.4.9`; fixed in `1.4.9`

## Machine-written summary

Summary written by Claude Haiku from the source advisory. Not reviewed by a person.

> openssl-encrypt versions before 1.4.9 do not properly validate key derivation function costs in crafted files, so processing a malicious file can exhaust memory and CPU before password verification. An attacker who can supply a crafted file to the software can crash or stall the process. Upgrade to openssl-encrypt 1.4.9 or later.

Written 1 Nov 2026.

## 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

- 8.7 High, CVSS 4.0: `CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N`, from CNA (VulnCheck)

- **CISA KEV:** Not listed.
- **EPSS:** 0.0050, the 43rd percentile, on 14 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

## Timeline

- 31 Oct 2026, 14:10 UTC: First seen by agentprime
- 31 Oct 2026, 14:10 UTC: [Confirmed by OSV](https://osv.dev/vulnerability/PYSEC-2026-3961)

## Sources

- [GitHub Advisory Database: GHSA-phmr-p567-q5g6](https://github.com/advisories/GHSA-phmr-p567-q5g6)
- [OSV: GHSA-phmr-p567-q5g6](https://osv.dev/vulnerability/GHSA-phmr-p567-q5g6)
- <https://github.com/jahlives/openssl_encrypt/security/advisories/GHSA-phmr-p567-q5g6>
- <https://www.vulncheck.com/advisories/openssl-encrypt-before-1.4.9-denial-of-service-via-unbounded-kdf-cost>

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-phmr-p567-q5g6>, 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-phmr-p567-q5g6/>. Everything for agents: <https://agentprime.io/llms.txt>.