CVE-2017-16881 — b3log Symphony (aka Sym) 2

b3log Symphony (aka Sym) 2.2.0 does not properly address XSS in JSON objects, as demonstrated by a crafted userAvatarURL value to /settings/avatar, related to processor/AdminProcessor.java, processor/ArticleProcessor.java, processor/UserProcessor.java, service/ArticleQueryService

01What is this vulnerability?

b3log Symphony (aka Sym) 2.2.0 does not properly address XSS in JSON objects, as demonstrated by a crafted userAvatarURL value to /settings/avatar, related to processor/AdminProcessor.java, processor/ArticleProcessor.java, processor/UserProcessor.java, service/ArticleQueryService.java, service/AvatarQueryService.java, and service/CommentQueryService.java.

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: 2017-11-18T13:29:00.207
• Last modified: 2026-05-13T00:24:29.033

09References

• github.com — https://github.com/b3log/symphony/issues/504
• github.com — https://github.com/b3log/symphony/issues/504