CVE-2017-9047
A buffer overflow was discovered in libxml2 20904-GITv2.9.4-16-g0741801.
Published May 18, 2017 · updated Oct 14, 2026 · xmlsoft libxml2
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.
Code
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No public source repository is identified for this product.
Timeline
Detection, updates, and resolution for this record.
May 18, 2017 · NIST NVD
Detected
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) whereupo
Oct 14, 2026 · NIST NVD
Updated
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) whereupo
Affected
- cpe xmlsoft/libxml22.9.4
Sources
- CVE.orgVulnerability recordCVE-2017-9047
Official CVE identifier
cve.org - FIRST EPSSExploitation probabilityCVE-2017-9047
30-day exploitation probability 3.2%
first.org - NIST NVDVulnerability recordCVE-2017-9047
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 cont
nvd.nist.gov