How severe is CVE-2026-8468?

No CVSS score has been assigned to CVE-2026-8468 yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by CVE-2026-8468?

CVE-2026-8468 affects the following packages: plug (Hex), plug (Hex), plug (Hex), plug (Hex), plug (Hex). Ecosystems affected: Hex.

How do I fix CVE-2026-8468?

Update plug to 1.15.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-8468 is resolved across your whole dependency graph.

How do I detect CVE-2026-8468 in my Hex dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for plug, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2026-8468 if there is no patch (or I can't update yet)?

Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.

Is CVE-2026-8468 actively exploited in the wild?

No public exploit code has been indexed for CVE-2026-8468 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2026-8468?

CVE-2026-8468 has an EPSS (Exploit Prediction Scoring System) score of 0.8%, placing it in the 56th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2026-8468?

CVE-2026-8468 is classified as CWE-770 (CWE-770). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2026-8468 published, and has it been updated?

CVE-2026-8468 was published on May 14, 2026 and was last updated on August 12, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

💧 Hex

Not in CISA KEV

CVE-2026-8468 — plug

Fix: elixir-plug/plug@2cb7958

CVE-2026-8468 is a CWE-770 vulnerability in plug. A fix is available for plug — see the affected versions and patch details below.

Unbounded buffer accumulation in multipart header parsing causes denial of service in plug

Also known asEEF-CVE-2026-8468GHSA-468c-vq7p-gh64

Published

May 14, 2026

Updated

Aug 12, 2026

Affected

5 pkgs

Patched

5 / 5

Exploits

None indexed

Exploitation data as of Sep 27, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for CVE-2026-8468.

EPSS Exploitation Probability

via FIRST.org ↗

0.8%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs56th percentile — riskier than 56% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

Real-World Exposure

5 pkgs affected

💧plug💧plug💧plug💧plug💧plug

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Hex packages — download data is not available via public APIs for these ecosystems.

Description

Summary

An Allocation of Resources Without Limits or Throttling vulnerability in Plug.Conn.read_part_headers/2 allows an unauthenticated attacker to exhaust server memory by sending a crafted multipart/form-data request, causing a denial of service.

Details

Plug.Conn.read_part_headers/2 in lib/plug/conn.ex does not obey its :length parameter. There is no upper bound on the size of the accumulated buffer. By contrast, the sibling function read_part_body has an explicit byte_size(acc) > length guard that stops accumulation once a limit is reached. No such guard exists in read_part_headers.

Impact

This is a denial-of-service vulnerability. Any application using Plug.Parsers with the :multipart parser, or calling Plug.Conn.read_part_headers/2 directly, is affected. An unauthenticated remote attacker can trigger the issue by sending crafted HTTP requests with no special privileges.

References

Intro Commit: https://github.com/elixir-plug/plug/commit/c52b2f32c90bccd718202bafccb5f95594e30183
Patch Commit: https://github.com/elixir-plug/plug/commit/d878b42efea9f12b243dc3e362a2ed048a798203

Affected Packages

5 total 5 fixed

Ecosystem	Package	Vulnerable range	Fix
💧Hex	`plug`	≥ 1.4.0&&< 1.15.4	1.15.4`mix deps.update plug`
💧Hex	`plug`	≥ 1.16.0&&< 1.16.3	1.16.3`mix deps.update plug`
💧Hex	`plug`	≥ 1.17.0&&< 1.17.1	1.17.1`mix deps.update plug`
💧Hex	`plug`	≥ 1.18.0&&< 1.18.2	1.18.2`mix deps.update plug`
💧Hex	`plug`	≥ 1.19.0&&< 1.19.2	1.19.2`mix deps.update plug`

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for plug, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update plug to 1.15.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-8468 is resolved across your whole dependency graph.
Workarounds
Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.

Frequently Asked Questions

### Summary An Allocation of Resources Without Limits or Throttling vulnerability in `Plug.Conn.read_part_headers/2` allows an unauthenticated attacker to exhaust server memory by sending a crafted `multipart/form-data` request, causing a denial of service. ### Details `Plug.Conn.read_part_headers/2` in `lib/plug/conn.ex` does not obey its `:length` parameter. There is no upper bound on the size of the accumulated buffer. By contrast, the sibling function `read_part_body` has an explicit `byte_size(acc) > length` guard that stops accumulation once a limit is reached. No such guard exists in