CVE-2019-10741 — K-9 Mail v5

K-9 Mail v5.600 can include the original quoted HTML code of a specially crafted, benign looking, email within (digitally signed) reply messages. The quoted part can contain conditional statements that show completely different text if opened in a different email client. This can

01What is this vulnerability?

K-9 Mail v5.600 can include the original quoted HTML code of a specially crafted, benign looking, email within (digitally signed) reply messages. The quoted part can contain conditional statements that show completely different text if opened in a different email client. This can be abused by an attacker to obtain valid S/MIME or PGP signatures for arbitrary content to be displayed to a third…

02Affected products

Vendor	Product	Versions
n	a / n/a	n/a

03Active exploitation status

Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.

04Recommended remediation

• Patch to a fixed version listed in the vendor advisory (see references below).
• Mitigate with WAF rules, network egress filters, or feature flags where the patch is not yet available.
• Hunt historical logs for exploitation indicators — see Detection signatures below.

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Ask SARA in chat to draft a starting detection for this CVE in your stack of choice.

07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

• Published: 2019-04-07T14:37:51.000Z
• Last modified: 2024-08-04T22:32:01.213Z

09References

• github.com — https://github.com/k9mail/k-9/issues/3925