# CVE-2023-41037: Cleartext Signed Message Signature Spoofing in openpgpjs > Attackers can spoof OpenPGP cleartext signatures by adding unsigned text, misleading users who rely on visual inspection rather than verified data. - **Severity:** Medium 4.3 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N`) - **Exploited in the wild:** Not known - **Login needed:** Not needed - **Attackable:** Over the internet - **Victim action needed:** A user has to click or open something - **Fix available:** Yes - **Published:** 29 Aug 2023 - **Updated:** 30 Sep 2024 - **Also known as:** GHSA-ch3c-v47x-4pgp ## What is CVE-2023-41037? CVE-2023-41037 is a medium-severity vulnerability in openpgpjs, published on 29 Aug 2023. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link. ### Official 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. Weakness: CWE-347 (Improper Verification of Cryptographic Signature) ## Which versions are affected by CVE-2023-41037? 4 open source packages ship an affected version, including openpgp. It affects 1 product. | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `openpgp` | npm | All versions | 4.10.11 | | `openpgp` | npm | All versions | 4.10.11 | | `openpgp` | npm | From 5.0.0 | 5.10.1 | | `openpgp` | npm | From 5.0.0 | 5.10.1 | Products: Openpgpjs Openpgpjs. ## How do I fix CVE-2023-41037? Upgrade openpgp to a fixed version for your release line: 4.10.11 or 5.10.1. ## Is CVE-2023-41037 being exploited? There is no known exploitation of CVE-2023-41037 in the wild and no public exploit code. ## Other vulnerabilities in openpgpjs - [CVE-2019-9153](https://insights.sbomify.com/CVE-2019-9153/): Message Signature Bypass in openpgp (high 7.5) - [CVE-2019-9154](https://insights.sbomify.com/CVE-2019-9154/): Improper Key Verification in openpgp (high 7.5) - [CVE-2015-8013](https://insights.sbomify.com/CVE-2015-8013/): OpenPGP 1.2.0 and earlier decrypts arbitrary messages (high 7.5) - [CVE-2019-9155](https://insights.sbomify.com/CVE-2019-9155/): Invalid Curve Attack in openpgp (medium 5.9) ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2023-41037 and fix it if it is affected. What it is: CVE-2023-41037 is a medium-severity vulnerability in openpgpjs, published on 29 Aug 2023. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link. Exploitation: There is no known exploitation of CVE-2023-41037 in the wild and no public exploit code. Affected packages and fixed versions: - openpgp (npm): affected all versions; fixed in 4.10.11 - openpgp (npm): affected all versions; fixed in 4.10.11 - openpgp (npm): affected from 5.0.0; fixed in 5.10.1 - openpgp (npm): affected from 5.0.0; fixed in 5.10.1 Task: 1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies. 2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it. 3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead. 4. Run the tests and summarise what changed and why. 5. If nothing in the project is affected, say so and change nothing. Reference: https://insights.sbomify.com/CVE-2023-41037/ (Markdown: https://insights.sbomify.com/CVE-2023-41037/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2023-41037 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-41037 - OSV: https://osv.dev/vulnerability/CVE-2023-41037 --- From sbomify Insights: https://insights.sbomify.com/CVE-2023-41037/ Summaries are generated and may contain mistakes; the official description above is the record.