github.com/imgproxy/imgproxy: Heap-based Buffer Overflow (ghsa:GHSA-hff9-5pqw-6w9f)
Published Sources: Hersteller
What is affected, what to do
Update github.com/imgproxy/imgproxy to version 4.0.16, github.com/imgproxy/imgproxy/v2 to version 4.0.16, github.com/imgproxy/imgproxy/v3 to version 4.0.16.
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Metrics
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Priority
No value is available for this vulnerability.
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CVSS v3
No value is available for this vulnerability.
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EPSS score
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- Severity
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Priority (0–325)
The priority score is a consolidated metric that condenses several individual signals into a single, action-guiding ranking: technical severity (CVSS), exploitation likelihood (EPSS), known-exploited status (KEV) and the context of the affected asset. The aim is to answer the only truly important question in vulnerability management: what first?
Read in glossary- 30.00 Methodology
Exploit maturity
An exploit is code or a technique that specifically uses a concrete vulnerability to force unintended behaviour — such as executing code or escalating privileges. It is the tool that turns a theoretical flaw into a practical attack.
Read in glossary- no public PoC known
KEV status
The KEV catalogue is a list maintained by the US authority CISA of vulnerabilities for which active exploitation in the wild has been confirmed. It answers not the question „how severe?“ but „is it already being attacked?“ — thereby sharply prioritising patching.
Read in glossary- —
- Published
CWE
CWE is a catalogue of typical weakness types in software and hardware — such as flawed input validation, unsafe memory handling or poor authentication. Where a CVE names a concrete vulnerability in a concrete product, a CWE describes the underlying class of defect.
Read in glossary- CWE-122, CWE-190
Classification under NIS2 and CRA
Rule-based classification from exploitation status and severity. It does not replace a case-by-case assessment.
NIS2
NIS2 is EU Directive (EU) 2022/2555 to raise the level of cybersecurity across the Union. It substantially broadens obligations compared with the first NIS directive: more sectors, mandatory risk management, staged reporting duties and personal accountability of senior management.
Read in glossary- High technical severity: assess and remediate the vulnerability in vulnerability handling under Art. 21(2)(e) NIS2 and document the decision.
CRA
The CRA is EU Regulation (EU) 2024/2847 setting horizontal cybersecurity requirements for „products with digital elements“ — from industrial controllers and software to connected consumer devices. For the first time manufacturers must ensure security across the entire product lifecycle, handle vulnerabilities and provide security updates.
Read in glossary- From 11.12.2027, Annex I Part II CRA requires manufacturers of affected products with digital elements to handle vulnerabilities without delay and provide security updates.
ISO/IEC 27001
ISO/IEC 27001 is the internationally leading standard for an information security management system (ISMS). It describes a risk-based, process-oriented framework to systematically plan, implement, review and improve information security.
Read in glossary- Control A.8.8, management of technical vulnerabilities: assess relevance to your systems, plan remediation and keep evidence.
Description
Summary
The ICO loader allocates data_size + BMP_FILE_HEADER_LEN bytes after reading a 32-bit attacker-controlled data_size. For data_size > UINT32_MAX - BMP_FILE_HEADER_LEN, the addition wraps before allocation. imgproxy then writes the ICO prefix and reads up to the original declared size starting 14 bytes into the undersized allocation. A network client can turn this heap overflow into remote denial of service or remote code execution.
Technical details
The vulnerable path is in vips/icoload.c at commit f4fedbb:
uint32_t data_size = GUINT32_FROM_LE(largest_image_header.data_size);
VipsPel *data = (VipsPel *) VIPS_MALLOC(NULL, data_size + BMP_FILE_HEADER_LEN);
void *actual_data = data + BMP_FILE_HEADER_LEN;
if (vips_foreign_load_read_full(ico->source, actual_data, data_size) <= 0) {
vips_error("vips_foreign_load_ico_header", "unable to read ICO image data from the source");
return -1;
}
The crafted directory entry contains:
data_size = 0xfffffff5 (4294967285)
data_offset = 22
BMP header size = 14
32-bit result = (0xfffffff5 + 14) mod 2^32 = 3
The allocation is therefore three bytes. actual_data points 14 bytes after the allocation base. The fixture contains 64 bytes after the ICO header, so the source callback copies those 64 bytes to an invalid destination before it can report that the declared multi-gigabyte payload is incomplete.
The complete source-to-sink path is:
- Attacker-controlled bytes begin with the ICO magic
00 00 01 00. - imgproxy identifies the source as ICO and dispatches it to
vips_icoload_source_go. vips_foreign_load_ico_headerreads the attacker-controlleddata_size.- The 32-bit addition wraps, and
VIPS_MALLOCreceives the value three. vips_foreign_load_read_fullpasses the originaldata_sizeto the Go source callback.- The callback writes the available source bytes through the invalid pointer, corrupting the process heap.
Impact
A crafted image can terminate the imgproxy process handling it or potentially lead to remote code execution due to heap corruption.
Source: GitHub Security Advisories
Affected products
The following versions are affected. Older releases of the same product line are also vulnerable unless stated otherwise.
| Affected versions | Fixed in | ||
|---|---|---|---|
| go | github.com/imgproxy/imgproxy |
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| go | github.com/imgproxy/imgproxy/v2 |
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| go | github.com/imgproxy/imgproxy/v3 |
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Vendors and products
Weakness classes (CWE)
CWE-122Heap-based Buffer Overflow
Variant
A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc().
Entry at MITRE CWE-122CWE-190Integer Overflow or Wraparound
Base
The product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.
Entry at MITRE CWE-190