What is CVE-2017-9048?

CVE-2017-9048 is a high-severity vulnerability in Xmlsoft Libxml2, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 7.5/10. Published 2017-05-18.

How severe is CVE-2017-9048?

High severity. CVSS v3 base score is 7.5 out of 10.

Is CVE-2017-9048 known to be exploited?

2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Buffer overflow in Xmlsoft Libxml2

CVE-2017-9048

libxml2 20904-GITv2.9.4-16-g0741801 is vulnerable to a stack-based buffer overflow. The function xmlSnprintfElementContent in valid.c is supposed to recursively dump the element content definition into a char buffer 'buf' of size 'size'. At the end of the routine, the function may strcat two more characters without checking whether the current strlen(buf) + 2 < size. This vulnerability causes programs that use libxml2, such as PHP, to crash.

Vulnerability class: Buffer Overflow

Published 2017-05-18 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.048 (91.8th percentile), scored 2026-10-06.

Low probability of exploitation in the next 30 days, but still tracked. 92nd percentile — 91.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.048 · newest: 0.048 · change: 0.000

Affected products

Xmlsoft Libxml2 — versions 2.9.4

Weakness classification (CWE)

CWE-119 — Improper Restriction of Operations within the Bounds of a Memory Buffer

Public proof-of-concept exploits

References

www.debian.org/security/2017/dsa-3952 (vendor-advisory)
security.gentoo.org/glsa/201711-01 (vendor-advisory)
www.openwall.com/lists/oss-security/2017/05/15/1 (Exploit, Patch, Mailing List, Third Party Advisory)
www.securityfocus.com/bid/98556 (VDB Entry, Third Party Advisory, vdb-entry)
lists.apache.org/thread.html/rf4c02775860db415b4955778a131c2795223f61cb8c6a4508… (mailing-list)
lists.apache.org/thread.html/r58af02e294bd07f487e2c64ffc0a29b837db5600e33b6e698… (mailing-list)

Frequently asked questions

What is CVE-2017-9048?: CVE-2017-9048 is a high-severity vulnerability in Xmlsoft Libxml2, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 7.5/10. Published 2017-05-18.
How severe is CVE-2017-9048?: High severity. CVSS v3 base score is 7.5 out of 10.
Is CVE-2017-9048 known to be exploited?: 2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.