Description
Allocation of Resources Without Limits or Throttling vulnerability in plug_project plug allows denial of service via unbounded buffer accumulation in multipart header parsing. 'Elixir.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. An unauthenticated remote attacker can exhaust server memory by sending a crafted multipart/form-data request, causing a denial of service. This issue affects plug from 1.4.0 before 1.15.4, 1.16.3, 1.17.1, 1.18.2, and 1.19.2.
References9
- cna.erlef.org/cves/CVE-2026-8466.html
- cna.erlef.org/cves/CVE-2026-8468.html
- github.com/elixir-plug/plug/commit/2cb7958d33030aa826b0c7404375…
- github.com/elixir-plug/plug/commit/33858427c7f2737d560a2e40a0c9…
- github.com/elixir-plug/plug/commit/aa69c5ece99c40ded88b8c6581ec…
- github.com/elixir-plug/plug/commit/d5dfffe25e975585227b1b85d247…
- github.com/elixir-plug/plug/commit/df812a1527bae9e941965e897308…
- github.com/elixir-plug/plug/security/advisories/GHSA-468c-vq7p-…
- osv.dev/vulnerability/EEF-CVE-2026-8468
Metrics
- CVSS 4.0
-
8.2
HIGH
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 1% percentile: 50 · as of 14 November 2026
- CWE
- CWE-770
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