CVE-2018-5548 — On BIG-IP APM 11

On BIG-IP APM 11.6.0-11.6.3, an insecure AES ECB mode is used for orig_uri parameter in an undisclosed /vdesk link of APM virtual server configured with an access profile, allowing a malicious user to build a redirect URI value using different blocks of cipher texts.

01What is this vulnerability?

On BIG-IP APM 11.6.0-11.6.3, an insecure AES ECB mode is used for orig_uri parameter in an undisclosed /vdesk link of APM virtual server configured with an access profile, allowing a malicious user to build a redirect URI value using different blocks of cipher texts.

02Affected products

Vendor	Product	Versions
F5 Networks, Inc.	BIG	IP APM — 11.6.0-11.6.3

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: 2018-09-13T14:00:00.000Z
• Last modified: 2024-09-16T19:41:32.544Z

09References

• support.f5.com — https://support.f5.com/csp/article/K66171422
• sbudella.altervista.org — http://sbudella.altervista.org/blog/20180911-cve-2018-5548.html
• www.securityfocus.com — http://www.securityfocus.com/bid/105353