CVE-2023-41037
As a result, malicious parties could add arbitrary text to a third-party Cleartext Signed Message, to lead the victim to believe that the arbitrary text was signed.
Does this matter?
Lower severity and a low EPSS score (0.35%). Track it; it rarely justifies an emergency change on its own.
Description
OpenPGP.js is a JavaScript implementation of the OpenPGP protocol. In affected versions OpenPGP Cleartext Signed Messages are cryptographically signed messages where the signed text is readable without special tools. These messages typically contain a "Hash: ..." header declaring the hash algorithm used to compute the signature digest. OpenPGP.js up to v5.9.0 ignored any data preceding the "Hash: ..." texts when verifying the signature. As a result, malicious parties could add arbitrary text to a third-party Cleartext Signed Message, to lead the victim to believe that the arbitrary text was signed. A user or application is vulnerable to said attack vector if it verifies the CleartextMessage by only checking the returned `verified` property, discarding the associated `data` information, and instead _visually trusting_ the contents of the original message. Since `verificationResult.data` would always contain the actual signed data, users and apps that check this information are not vulnerable. Similarly, given a CleartextMessage object, retrieving the data using `getText()` or the `text` field returns only the contents that are considered when verifying the signature. Finally, re-armoring a CleartextMessage object (using `armor()` will also result in a "sanitised" version, with the extraneous text being removed. This issue has been addressed in version 5.10.1 (current stable version) which will reject messages when calling `openpgp.readCleartextMessage()` and in version 4.10.11 (legacy version) which will will reject messages when calling `openpgp.cleartext.readArmored()`. Users are advised to upgrade. Users unable to upgrade should check the contents of `verificationResult.data` to see what data was actually signed, rather than visually trusting the contents of the armored message.
- CVSS 3.1
- 4.3 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N
- EPSS
- 0.35% probability · 29th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-347
- Affected
- openpgpjs/openpgpjs
- Source
- security-advisories@github.com
References
- https://github.com/openpgpjs/openpgpjs/commit/6b43e02a254853f5ff508ebd1b07541f78b7c566Patch
- https://github.com/openpgpjs/openpgpjs/security/advisories/GHSA-ch3c-v47x-4pgpExploit, Vendor Advisory
- https://github.com/openpgpjs/openpgpjs/commit/6b43e02a254853f5ff508ebd1b07541f78b7c566Patch
- https://github.com/openpgpjs/openpgpjs/security/advisories/GHSA-ch3c-v47x-4pgpExploit, Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.