Vulnerability in Haxx (CVE-2026-3783)
Summary
Vulnerability in Haxx (CVE-2026-3783). Risk of unauthorized operations or information disclosure. Exploitable via machine.
Original description
The description as published by the source.
When an OAuth2 bearer token is used for an HTTP(S) transfer, and that transfer
performs a redirect to a second URL, curl could leak that token to the second
hostname under some circumstances.
If the hostname that the first request is redirected to has information in the
used .netrc file, with either of the machine or default keywords, curl
would pass on the bearer token set for the first host also to the second one.
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-3783 has been found in Haxx.
Attackers can target a specific entry point like machine over the network to misuse the product.
Risk of unauthorized operations or information disclosure. CVSS score: 5.3/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Haxx CVE-2026-3783" on the vendor's site.
CVE-2026-3783 (Haxx) — CWE-522 / CVSS v3 5.3
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Attack surface: machine / default
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-522) exists in Haxx. Attackers reach the vulnerable code path via machine without authentication.
Check the vendor advisory for the affected versions of Haxx. Attack surface: machine / default.
Severity: Medium (CVSS 5.3/10). Risk of unauthorized operations or information disclosure.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'Haxx' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'Haxx' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
Haxxを grep し、稼働しているサービス・バージョンを把握する。 -
2Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Fix status by distribution
Fixed packages published by each distribution for this CVE
- Alpine Linux ALPINE-CVE-2026-3783 curl Fixed in: 8.19.0-r0
- Debian DEBIAN-CVE-2026-3783 curl
- Ubuntu UBUNTU-CVE-2026-3783 curl Fixed in: 7.68.0-1ubuntu2.25+esm3
References
- advisory openwall.com
- exploit hackerone.com
- patch curl.se
- patch curl.se