CVE-2019-13948 — SyGuestBook A5 Version 1

SyGuestBook A5 Version 1.2 allows stored XSS because the isValidData function in include/functions.php does not properly block XSS payloads, as demonstrated by a crafted use of the onerror attribute of an IMG element.

01What is this vulnerability?

SyGuestBook A5 Version 1.2 allows stored XSS because the isValidData function in include/functions.php does not properly block XSS payloads, as demonstrated by a crafted use of the onerror attribute of an IMG element.

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: 2019-07-18T15:56:39.000Z
• Last modified: 2024-08-05T00:05:44.068Z

09References

• fragrant10.github.io — https://fragrant10.github.io/2019/02/22/SyGuestBookA5%E4%BB%A3%E7%A0%81%E5%AE%A1…
• github.com — https://github.com/fragrant10/fragrant10.github.io/blob/master/_posts/2019-02-22…