CVE-2026-128242
actix-http before 3.20.1 and actix-web before 4.18.2 Decompression Bomb DoS via encoding::Decoder
actix-http before 3.20.1 and actix-web before 4.18.2 contain an unbounded decompression vulnerability in encoding::Decoder that lets remote attackers exhaust memory and CPU via compressed bodies. Attackers can send small highly compressed gzip, deflate, Brotli or zstd request bodies to Json, Form, Bytes or String extractors, or serve them to awc clients, causing denial of service.
Fixes and workarounds
Fix
The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.
Source: CNA: VulnCheckFix
The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.
Source: CNA: VulnCheckAffected products and versions
| Product | Versions | Authority |
|---|---|---|
| actix-http actix actix-http
cargo |
≥ 0; < 3.20.1 (affected, semver)
Other versions: unaffected |
CNA: VulnCheck |
| actix-web actix actix-web
cargo |
≥ 0; < 4.18.2 (affected, semver)
Other versions: unaffected |
CNA: VulnCheck |
Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.
CVSS assessments
| Version / score | Vector | Authority |
|---|---|---|
| 4.0 / 8.7 high |
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N | CNA: VulnCheck |
| 3.1 / 7.5 high |
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | CNA: VulnCheck |
| 4.0 / 8.7 high |
CVSS:4.0/AV:N/AC:L/AT:N/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 | NVD: [email protected] |
| 3.1 / 7.5 high |
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | NVD: [email protected] |
Exploit evidence
No exploit evidence in collected sources. This is not proof of no exploitation.
References
- https://github.com/actix/actix-web/security/advisories/GHSA-qph8-7859-gq2fCNA: VulnCheck · vendor-advisory
- https://rustsec.org/advisories/RUSTSEC-2026-0448.htmlCNA: VulnCheck · third-party-advisory
- https://github.com/actix/actix-web/commit/41b54d23ea04f66758c15de7e4ab18325cd25280CNA: VulnCheck · patch
- https://github.com/actix/actix-web/commit/0d0be61bd757027bfcecbc53df1b7a600f21ecd0CNA: VulnCheck · patch
- https://github.com/actix/actix-web/blob/actix-http-v3.20.0/actix-http/src/encoding/decoder.rs#L239-L301CNA: VulnCheck · technical-description
- https://github.com/actix/actix-web/releases/tag/actix-http-v3.20.1CNA: VulnCheck · release-notes
- https://github.com/actix/actix-web/releases/tag/actix-web-v4.18.2CNA: VulnCheck · release-notes
- https://github.com/actix/actix-webCNA: VulnCheck · product
- https://www.vulncheck.com/advisories/actix-http-before-3.20.1-and-actix-web-before-4.18.2-decompression-bomb-dos-via-encoding-decoderCNA: VulnCheck · third-party-advisory
- https://github.com/actix/actix-web[email protected]
- https://github.com/actix/actix-web/blob/actix-http-v3.20.0/actix-http/src/encoding/decoder.rs#L239-L301[email protected]
- https://github.com/actix/actix-web/commit/0d0be61bd757027bfcecbc53df1b7a600f21ecd0[email protected]
- https://github.com/actix/actix-web/commit/41b54d23ea04f66758c15de7e4ab18325cd25280[email protected]
- https://github.com/actix/actix-web/releases/tag/actix-http-v3.20.1[email protected]
- https://github.com/actix/actix-web/releases/tag/actix-web-v4.18.2[email protected]
- https://github.com/actix/actix-web/security/advisories/GHSA-qph8-7859-gq2f[email protected]
- https://rustsec.org/advisories/RUSTSEC-2026-0448.html[email protected]
- https://www.vulncheck.com/advisories/actix-http-before-3.20.1-and-actix-web-before-4.18.2-decompression-bomb-dos-via-encoding-decoder[email protected]
For agents and automation
Read public disclosures for free as Markdown or JSON. Compatible browsers also expose native WebMCP tools to search disclosures, read this page, and discover API access.
Use the ontology-linked Cyber API with x402 pay per request, or a Y2 Pro or Elite API key with the intel:cyber scope.
Endpoints and access details
https://api.y2.dev/api/v2/cyber/cveshttps://api.y2.dev/api/v2/cyber/cves/{cveId}
A workspace owner or admin can create a Pro or Elite API key. Send Authorization: Bearer <Y2_API_KEY> from your trusted agent runtime.
For x402, omit Authorization and read the HTTP 402 payment challenge before signing a retry. Public browser tools do not make payments.