CVE-2017-17715 — The saveFile method in MediaController

The saveFile method in MediaController.java in the Telegram Messenger application before 2017-12-08 for Android allows directory traversal via a pathname obtained in a file-transfer request from a remote peer, as demonstrated by writing to tgnet.dat or tgnet.dat.bak.

01What is this vulnerability?

The saveFile method in MediaController.java in the Telegram Messenger application before 2017-12-08 for Android allows directory traversal via a pathname obtained in a file-transfer request from a remote peer, as demonstrated by writing to tgnet.dat or tgnet.dat.bak.

02Affected products

No structured affected-product list available — see references below for vendor advisories.

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: 2017-12-16T19:29:00.260
• Last modified: 2026-05-13T00:24:29.033

09References

• bugs.chromium.org — https://bugs.chromium.org/p/project-zero/issues/detail?id=1470
• bugs.chromium.org — https://bugs.chromium.org/p/project-zero/issues/detail?id=1470