GHSA-j6xh-q826-55jw CVE-2013-4179 PYSEC-2026-875
OpenStack Compute (Nova) vulnerable to denial of service via XML Entity Expansion attack
Medium
PyPI
- Severity
- Medium
- The publisher's own rating, not a CVSS score
- Exploit chance (EPSS)
- 2.73%
- Chance of exploitation in the next 30 days. Higher than 86.06% of scored vulnerabilities.
- Known exploited
- No
- Not in CISA's catalog
- Weakness
- CWE-119 Improper Restriction of Operations within the Bounds of a Memory Buffer
- Fix
2013.2- Upgrade nova to this version or later
Description
The security group extension in OpenStack Compute (Nova) Grizzly 2013.1.3, Havana before havana-3, and earlier allows remote attackers to cause a denial of service (resource consumption and crash) via an XML Entity Expansion (XEE) attack. NOTE: this issue is due to an incomplete fix for CVE-2013-1664.
Affected versions
PyPI
| Package | Vulnerable | Fixed in |
|---|---|---|
| nova | < 2013.2 |
2013.2 |
How to fix
Move to the fixed version or later with your package manager, update the lockfile, and run your tests. If the package only arrives through another dependency, upgrade that dependency first. If none of its releases pulls a fixed version yet, force the version with your package manager's override.
nova PyPI → 2013.2
- pip
pip install --upgrade "nova>=2013.2"- poetry
poetry add "nova>=2013.2"- uv
uv add "nova>=2013.2"
Weakness
CWE-119: Improper Restriction of Operations within the Bounds of a Memory Buffer
The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.
How to prevent it
- Requirements: Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, many languages that perform their own memory management, such as Java and Perl, are not subject to buffer overflows. Other languages, such as Ada and C#, typically provide overflow protection, but the protection can be disabled by the programmer. Be wary that a language's interface to native code may still be subject to overflows, even if the language itself is theoretically safe.
- Architecture and Design: Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. Examples include the Safe C String Library (SafeStr) by Messier and Viega [REF-57], and the Strsafe.h library from Microsoft [REF-56]. These libraries provide safer versions of overflow-prone string-handling functions.
- Operation, Build and Compilation: Use automatic buffer overflow detection mechanisms that are offered by certain compilers or compiler extensions. Examples include: the Microsoft Visual Studio /GS flag, Fedora/Red Hat FORTIFY_SOURCE GCC flag, StackGuard, and ProPolice, which provide various mechanisms including canary-based detection and range/index checking. D3-SFCV (Stack Frame Canary Validation) from D3FEND [REF-1334] discusses canary-based detection in detail.
- Implementation: Consider adhering to the following rules when allocating and managing an application's memory: Double check that the buffer is as large as specified. When using functions that accept a number of bytes to copy, such as strncpy(), be aware that if the destination buffer size is equal to the source buffer size, it may not NULL-terminate the string. Check buffer boundaries if accessing the buffer in a loop and make sure there is no danger of writing past the allocated space. If necessary, truncate all input strings to a reasonable length before passing them to the copy and concatenation functions.
- Operation, Build and Compilation: Run or compile the software using features or extensions that randomly arrange the positions of a program's executable and libraries in memory. Because this makes the addresses unpredictable, it can prevent an attacker from reliably jumping to exploitable code. Examples include Address Space Layout Randomization (ASLR) [REF-58] [REF-60] and Position-Independent Executables (PIE) [REF-64]. Imported modules may be similarly realigned if their default memory addresses conflict with other modules, in a process known as "rebasing" (for Windows) and "prelinking" (for Linux) [REF-1332] using randomly generated addresses. ASLR for libraries cannot be used in conjunction with prelink since it would require relocating the libraries at run-time, defeating the whole purpose of prelinking. For more information on these techniques see D3-SAOR (Segment Address Offset Randomization) from D3FEND [REF-1335].
- Operation: Use a CPU and operating system that offers Data Execution Protection (using hardware NX or XD bits) or the equivalent techniques that simulate this feature in software, such as PaX [REF-60] [REF-61]. These techniques ensure that any instruction executed is exclusively at a memory address that is part of the code segment. For more information on these techniques see D3-PSEP (Process Segment Execution Prevention) from D3FEND [REF-1336].
- Implementation: Replace unbounded copy functions with analogous functions that support length arguments, such as strcpy with strncpy. Create these if they are not available.
References
Advisories
Packages
Other links
Timeline
- Published
- Last updated by the source
- Latest EPSS score
Related advisories
| Advisory | Severity | Why it's related |
|---|---|---|
| GHSA-mfg3-p6m3-gjgr OpenStack Nova: Nova scheduler hint injection bypasses Placement resource claims and scheduling constraints | High | Also affects nova |
| GHSA-m4f3-qp2w-gwh6 OpenStack Nova calls qemu-img without format restrictions for resize | High | Also affects nova |
| GHSA-rm86-h44c-2r2m OpenStack Nova vulnerable to unauthorized access to potentially sensitive data | Medium | Also affects nova |
| GHSA-r4v4-w9pv-6fph OpenStack Cinder, Glance, and Nova vulnerable to arbitrary file access | Medium | Also affects nova |
| GHSA-7h75-hwxx-qpgc OpenStack Cinder, glance, and Nova vulnerable to Path Traversal | Medium | Also affects nova |
| GHSA-v725-c588-h936 OpenStack Nova Changing vnic_type breaks compute service restart | Low | Also affects nova |
| GHSA-22jm-4hxw-35jf OpenStack Nova can leak consoleauth token into log files | Low | Also affects nova |
| GHSA-43cm-73px-5v4m OpenStack Compute (Nova) Resource limit circumvention in Nova private flavors | Low | Also affects nova |
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