CVE-2024-56159
Server source code is exposed to the public if sourcemaps are enabled
- Published
- Updated
- Reserved
- Assigned by
- GitHub_M
Description
Astro is a web framework for content-driven websites. A bug in the build process allows any unauthenticated user to read parts of the server source code. During build, along with client assets such as css and font files, the sourcemap files **for the server code** are moved to a publicly-accessible folder. Any outside party can read them with an unauthorized HTTP GET request to the same server hosting the rest of the website. While some server files are hashed, making their access obscure, the files corresponding to the file system router (those in `src/pages`) are predictably named. For example. the sourcemap file for `src/pages/index.astro` gets named `dist/client/pages/index.astro.mjs.map`. This vulnerability is the root cause of issue #12703, which links to a simple stackblitz project demonstrating the vulnerability. Upon build, notice the contents of the `dist/client` (referred to as `config.build.client` in astro code) folder. All astro servers make the folder in question accessible to the public internet without any authentication. It contains `.map` files corresponding to the code that runs on the server. All **server-output** projects on Astro 5 versions **v5.0.3** through **v5.0.7**, that have **sourcemaps enabled**, either directly or through an add-on such as `sentry`, are affected. The fix for **server-output** projects was released in **[email protected]**. Additionally, all **static-output** projects built using Astro 4 versions **4.16.17 or older**, or Astro 5 versions **5.0.8 or older**, that have **sourcemaps enabled** are also affected. The fix for **static-output** projects was released in **[email protected]**, and backported to Astro v4 in **[email protected]**. The immediate impact is limited to source code. Any secrets or environment variables are not exposed unless they are present verbatim in the source code. There is no immediate loss of integrity within the the vulnerable server. However, it is possible to subsequently discover another vulnerability via the revealed source code . There is no immediate impact to availability of the vulnerable server. However, the presence of an unsafe regular expression, for example, can quickly be exploited to subsequently compromise the availability. The fix for **server-output** projects was released in **[email protected]**, and the fix for **static-output** projects was released in **[email protected]** and backported to Astro v4 in **[email protected]**. Users are advised to update immediately if they are using sourcemaps or an integration that enables sourcemaps.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 4.0 | High7.8 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:H/SI:L/SA:L |
| NVDNVD · Analyzed | 4.0 | High7.8 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:H/SI:L/SA:L/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 (exploitation in 30 days)
- 1.5% · top 25% of all CVEs (6 Nov 2026)
- CISA SSVC
- Exploitation: poc · Automatable: yes · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.8.
Weakness
Affected products
Affected packages
From reviewed advisories of the GitHub Advisory Database.
References (4)
- https://github.com/withastro/astro/security/advisories/GHSA-49w6-73cw-chjr (opens in a new tab)x_refsource_CONFIRMexploit
- https://github.com/withastro/astro/issues/12703 (opens in a new tab)x_refsource_MISC
- https://github.com/getsentry/sentry-javascript/blob/develop/packages/astro/src/integration/index.ts#L50 (opens in a new tab)x_refsource_MISC
- https://github.com/withastro/astro/blob/176fe9f113fd912f9b61e848b00bbcfecd6d5c2c/packages/astro/src/core/build/static-build.ts#L139 (opens in a new tab)x_refsource_MISC
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-49w6-73cw-chjr (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2024-56159)Record last updated .