CVE-2017-9047
Description
A buffer overflow was discovered in libxml2 20904-GITv2.9.4-16-g0741801. The function xmlSnprintfElementContent in valid.c is supposed to recursively dump the element content definition into a char buffer 'buf' of size 'size'. The variable len is assigned strlen(buf). If the content->type is XML_ELEMENT_CONTENT_ELEMENT, then (i) the content->prefix is appended to buf (if it actually fits) whereupon (ii) content->name is written to the buffer. However, the check for whether the content->name actually fits also uses 'len' rather than the updated buffer length strlen(buf). This allows us to write about "size" many bytes beyond the allocated memory. This vulnerability causes programs that use libxml2, such as PHP, to crash.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.
✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
OS impact
| OS | Version | Status | Fixed in |
|---|---|---|---|
| sles | affected | | |
| debian | bookworm | fixed | 2.9.4+dfsg1-3.1 |
| debian | bullseye | fixed | 2.9.4+dfsg1-3.1 |
| debian | forky | fixed | 2.9.4+dfsg1-3.1 |
| debian | sid | fixed | 2.9.4+dfsg1-3.1 |
| debian | trixie | fixed | 2.9.4+dfsg1-3.1 |
Application impact
| Vendor | Product | Versions | Fixed |
|---|---|---|---|
| xmlsoft | libxml2 | 2.9.4 | |
References
- http://www.debian.org/security/2017/dsa-3952
- http://www.openwall.com/lists/oss-security/2017/05/15/1
- http://www.securityfocus.com/bid/98599
- https://lists.apache.org/thread.html/r58af02e294bd07f487e2c64ffc0a29b837db5600e33b6e698b9d696b%40%3Cissues.bookkeeper.apache.org%3E
- https://lists.apache.org/thread.html/rf4c02775860db415b4955778a131c2795223f61cb8c6a450893651e4%40%3Cissues.bookkeeper.apache.org%3E
- https://security.gentoo.org/glsa/201711-01
- https://www.suse.com/security/cve/CVE-2017-9047.html
- https://security-tracker.debian.org/tracker/CVE-2017-9047
CWEs
CWE-119
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.