glibc: Out-of-bounds Write
CVE-2024-2961 is a high-severity out-of-bounds write vulnerability in glibc from The GNU C Library, with a CVSS 3.1 base score of 7.3 out of 10. It can be exploited with local access to the system by an unauthenticated attacker, without any action from a user. The record lists version 2.40 as the first without the flaw, so updating glibc to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 88.3% chance of exploitation within 30 days, which is in the top 0.23% of all scored CVEs.
Exploitation in the next 30 days is more likely than not, according to EPSS.
What to do
- Update glibc to 2.40 or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| The GNU C Library | glibc | 2.1.93 up to, but not including, 2.40 | 2.40 |
| Siemens | SIMATIC S7-1500 CPU 1518-4 PN/DP MFP | V3.1.5 and later | Not stated |
| Siemens | SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP | V3.1.5 and later | Not stated |
| Siemens | SIPLUS S7-1500 CPU 1518-4 PN/DP MFP | V3.1.5 and later | Not stated |
| NetApp | Active Iq Unified Manager | Not specified in the record | Not stated |
| Debian | Debian Linux | 10.0 | Not stated |
| NetApp | Hci H300s Firmware | Not specified in the record | Not stated |
| NetApp | Hci H500s Firmware | Not specified in the record | Not stated |
| NetApp | Hci H700s Firmware | Not specified in the record | Not stated |
| NetApp | Hci H410s Firmware | Not specified in the record | Not stated |
| NetApp | Hci H410c Firmware | Not specified in the record | Not stated |
| NetApp | Hci H610c Firmware | Not specified in the record | Not stated |
| NetApp | Hci H610s Firmware | Not specified in the record | Not stated |
| NetApp | Hci H615c Firmware | Not specified in the record | Not stated |
| NetApp | Hci Compute Node | Not specified in the record | Not stated |
| NetApp | Ontap Select Deploy Administration Utility | Not specified in the record | Not stated |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- LocalThe attacker needs local access or must trick a user into running something.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- LowSome restricted data can be read.
- Integrity
- LowLimited modification of data is possible.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H. Scored by CISA (ADP).
Official description
The iconv() function in the GNU C Library versions 2.39 and older may overflow the output buffer passed to it by up to 4 bytes when converting strings to the ISO-2022-CN-EXT character set, which may be used to crash an application or overwrite a neighbouring variable.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Out-of-bounds Write
The product writes data past the end, or before the beginning, of the intended buffer.
How developers prevent this class of flaw
- 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.
- 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, and the Strsafe.h library from Microsoft. These libraries provide safer versions of overflow-prone string-handling functions.
- 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 discusses canary-based detection in detail.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: poc, automatable: no, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Third-party and government advisories
- openwall.com/lists/oss-security/2024/04/17/9Mailing List, Third Party Advisory
- openwall.com/lists/oss-security/2024/04/18/4Mailing List, Third Party Advisory
- openwall.com/lists/oss-security/2024/04/24/2Mailing List, Third Party Advisory
- openwall.com/lists/oss-security/2024/05/27/1Mailing List, Third Party Advisory
- openwall.com/lists/oss-security/2024/05/27/2Mailing List, Third Party Advisory
- openwall.com/lists/oss-security/2024/05/27/3Mailing List, Third Party Advisory
- openwall.com/lists/oss-security/2024/05/27/4Mailing List, Third Party Advisory
- openwall.com/lists/oss-security/2024/05/27/5Mailing List, Third Party Advisory
- openwall.com/lists/oss-security/2024/05/27/6Mailing List, Third Party Advisory
- openwall.com/lists/oss-security/2024/07/22/5Mailing List, Third Party Advisory
- lists.debian.org/debian-lts-announce/2024/05/msg00001.htmlMailing List, Third Party Advisory
- security.netapp.com/advisory/ntap-20240531-0002/Third Party Advisory
- sourceware.org/git/?p=glibc.git;a=blob;f=advisories/GLIBC-SA-2024-0004Third Party Advisory
Other references
Other vulnerabilities in glibc
- 7.0 High severity
- 7.7 High severity
- 7.3 High severity
- 7.5 High severity
- 9.8 Critical severity
- 7.5 High severity
Recent Out-of-bounds Write vulnerabilities
- 8.8 High severity
- 9.8 Critical severity
- 9.8 Critical severity
- 8.8 High severity
- 8.8 High severity
- 7.8 High severity
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