CVE-2017-8923
9.8
CRITICAL · CVSS 3.1 · EPSS 7.2% (pctl 94)
In your normal cycle
Critical by CVSS (9.8), but no sign of active exploitation.
Description
The zend_string_extend function in Zend/zend_string.h in PHP through 7.1.5 does not prevent changes to string objects that result in a negative length, which allows remote attackers to cause a denial of service (application crash) or possibly have unspecified other impact by leveraging a script's use of .= with a long string.
Scoring
| CVSS | 9.8 (CRITICAL, v3.1) |
|---|---|
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| EPSS | 7.19% — more likely to be exploited than 94% of all CVEs |
| Weakness | CWE-787 |
| On CISA KEV | no |
| Public exploit | none known |
| Published | 2017-05-12 |
| Last modified | 2026-06-17 |
Affected (1)
| Vendor | Product |
|---|---|
| php | php |
References
→ the Explorer · watch your stack · NVD