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undici vulnerable to Denial of Service via unbounded decompression of compressed responses

Type: advisorySource: OSV1 source record

### Impact The `interceptors.decompress()` interceptor decompresses HTTP response bodies according to the untrusted `Content-Encoding` header. The number of decompression layers is capped at 5, but the total decompressed output size is not bounded and there is no option to limit it. A malicious or faulty upstream can return a small compressed payload (a compression bomb) that expands to hundreds of megabytes or gigabytes in client memory, exhausting memory and causing the Node.js process to crash or become unresponsive. Any application using the decompress interceptor to read responses from untrusted or compromised upstreams is affected. ### Patches Upgrade to `7.29.1` or `8.10.2`. The interceptor now accepts a `maxSize` option (default 64 MiB) and rejects responses whose decompressed output exceeds it with a `ResponseExceededMaxSizeError`. ### Workarounds Once upgraded, set a conservative `maxSize` on the interceptor. Before upgrading, avoid using `interceptors.decompress()` with untrusted upstreams, or apply a custom interceptor that enforces a decompressed output size limit.

Announced Source revision 1
Original source ↗

GHSA-3xpg-4rpp-hhhm

Primary source · Revision 1

Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.

Security context

Source reference: osv:GHSA-3xpg-4rpp-hhhm

undici

Source reference: /affected/0/package/name

Affected versions
Not stated in this record
Fixed versions
7.29.1

Source reference: /affected/0/ranges

Prerequisites
Not stated in this record

undici

Source reference: /affected/1/package/name

Affected versions
Not stated in this record
Fixed versions
8.10.2

Source reference: /affected/1/ranges

Prerequisites
Not stated in this record

Structured affected-version data

Original package identities and version rules from this source.

[
  {
    "ranges": [
      {
        "type": "SEMVER",
        "events": [
          {
            "introduced": "7.15.0"
          },
          {
            "fixed": "7.29.1"
          }
        ]
      }
    ],
    "package": {
      "name": "undici",
      "purl": "pkg:npm/undici",
      "ecosystem": "npm"
    },
    "database_specific": {
      "source": "https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/09/GHSA-3xpg-4rpp-hhhm/GHSA-3xpg-4rpp-hhhm.json"
    }
  },
  {
    "ranges": [
      {
        "type": "SEMVER",
        "events": [
          {
            "introduced": "8.0.0"
          },
          {
            "fixed": "8.10.2"
          }
        ]
      }
    ],
    "package": {
      "name": "undici",
      "purl": "pkg:npm/undici",
      "ecosystem": "npm"
    },
    "database_specific": {
      "source": "https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/09/GHSA-3xpg-4rpp-hhhm/GHSA-3xpg-4rpp-hhhm.json"
    }
  }
]
Related CVEs
CVE-2026-84890

Source reference: /aliases

Publisher severity

No explicit severity was provided.

Event
#31149 · Revision 1
Added to Heist Feed
Publisher date
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