Vulnerability in axios (CVE-2026-101903)
Summary
Vulnerability in axios (CVE-2026-101903). Risk of unauthorized operations or information disclosure. Exploitable via config.url. Mitigation: upgrade to 1.20.0 or later.
Original description
The description as published by the source.
Summary
Axios for Node.js parses data: URLs in lib/helpers/fromDataURI.js. The current RFC-2397 parser uses a regular expression whose media type groups allow / inside both sides of the type/subtype match. A malformed data: URL containing many slashes and no comma forces the JavaScript regex engine to try many possible placements for the separator before failing.
Applications are affected when they pass untrusted URL strings to axios and do not reject or constrain data: URLs before axios parses them.
Impact
An attacker can make the Node.js event loop spend significant synchronous CPU time parsing a single malformed URL. In a server that accepts a URL from an HTTP request and calls axios.get(url), this can block unrelated requests and health checks until parsing completes.
The issue is availability-only. It does not disclose data or modify requests.
Affected Functionality
Affected:
- Node.js HTTP adapter data URL handling.
axios.get()or equivalent calls whereconfig.urlhas thedata:protocol.
Not affected:
- Browser fetch/XHR URL handling.
- Node requests where the application rejects
data:URLs before calling axios. - Older checked
0.xdata URL parser shape unless separately proven vulnerable.
Technical Details
lib/helpers/fromDataURI.js contains:
const DATA_URL_PATTERN = /^([^,;]+\/[^,;]+)?((?:;[^,;=]+=[^,;]+)*)(;base64)?,([\s\S]*)$/;
The [^,;]+ groups include /, so a long string of slashes without a comma…
Source: NIST National Vulnerability Database NVD GitHub Advisory
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-2026-101903 has been found in axios.
Attackers can target a specific entry point like config.url over the network to misuse the product.
Risk of unauthorized operations or information disclosure.
What to do: upgrade axios to 1.20.0 or later.
If unsure, ask your IT team or search "axios CVE-2026-101903" on the vendor's site.
CVE-2026-101903 (axios) — CWE-1333
Attack surface: config.url / timeout / fromDataURI / axios
Patched: 1.20.0 — apply immediately
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-1333) exists in axios. Attackers reach the vulnerable code path via config.url.
Check the vendor advisory for the affected versions of axios. Attack surface: config.url / timeout / fromDataURI / axios.
Severity: ?. Risk of unauthorized operations or information disclosure.
Update to 1.20.0.
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 'axios' . 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 'axios' . | 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
axiosを grep し、稼働しているサービス・バージョンを把握する。 -
2Apply patch patch
Upgrade axios to 1.20.0ステージング環境で 1.20.0 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
-
3Post-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。
Affected packages
Fix status by distribution
Fixed packages published by each distribution for this CVE
- Debian DEBIAN-CVE-2026-101903 node-axios
- Ubuntu UBUNTU-CVE-2026-101903 node-axios
References
- advisory nvd.nist.gov
- package github.com
- web github.com
- web github.com
- web github.com
- web github.com
- web github.com