CVE-2026-87864 IMAP APPEND plus CRLF conversion command injection
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Published
Updated
Check this codebase for CVE-2026-87864 and fix it if it is affected.
What it is: CVE-2026-87864 is a vulnerability in curl, published on 20 Oct 2026.
Exploitation: There is no known exploitation of CVE-2026-87864 in the wild and no public exploit code.
Affected product: curl. No package-level version data is available, so check the vendor advisory linked from the reference page.
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-2026-87864/ (Markdown: https://insights.sbomify.com/CVE-2026-87864/index.md)
- Exploited in the wild
- Not known
- Fix
- Available
What is CVE-2026-87864?
CVE-2026-87864 is a vulnerability in curl, published on 20 Oct 2026.
Official description
Enabling `CURLOPT_CRLF` causes curl to advertise the raw input byte count in the `IMAP APPEND {N}` literal while transmitting line-ending expanded data. The server reads only $N$ bytes for the payload, causing the remaining overflow bytes to be interpreted and executed as pipelined IMAP commands within the authenticated session.
Which versions are affected by CVE-2026-87864?
How do I fix CVE-2026-87864?
Upgrade to a fixed version.
Is CVE-2026-87864 being exploited?
There is no known exploitation of CVE-2026-87864 in the wild and no public exploit code.
Sources
Also known as ALPINE-CVE-2026-87864, AZL-109926, AZL-109980, AZL-110025, AZL-110130, AZL-110223 and 9 more.