Security readout for executives and security teams
Plain-English summary
CVE-2020-27618 is a denial-of-service flaw in glibc's iconv conversion code. On affected systems, malformed input in specific IBM multibyte encodings can cause an application to loop indefinitely, consuming availability rather than exposing data.
Executive priority
Treat as a routine but real availability risk. It is not supported as actively exploited in the provided evidence, but core library exposure can be widespread, so include it in normal OS patch cycles.
Technical view
glibc 2.32 and earlier fail to advance input state in iconv when handling invalid multibyte sequences for IBM1364, IBM1371, IBM1388, IBM1390, and IBM1399. The assigned weakness is CWE-835, infinite loop. CVSS 3.1 is 5.5 with local attack vector and high availability impact.
Likely exposure
Exposure is most relevant on Linux or appliance platforms using glibc/libc6 2.32 or earlier, especially applications that invoke iconv on untrusted local input using the named IBM encodings. The source bundle does not identify broad remote exposure.
Exploitation context
The CVE is not listed as CISA KEV, and the provided sources do not state active exploitation. The CVSS vector indicates local access with low privileges, no user interaction, and availability-only impact.
Researcher notes
The affected-product metadata in the bundle is incomplete, but the CVE description clearly names glibc/libc6 2.32 and earlier. Validate downstream fixed versions through vendor advisories rather than assuming one universal package version.
Mitigation direction
- Apply glibc/libc6 security updates from the operating system or appliance vendor.
- Review Gentoo, Debian, Oracle, and NetApp advisories for product-specific update guidance.
- Prioritize multi-user systems and services processing untrusted local files or job input.
- If patch status is unclear, check current vendor guidance before accepting residual risk.
Validation and detection
- Inventory systems running glibc/libc6 2.32 or earlier.
- Confirm package advisories or changelogs reference CVE-2020-27618 remediation.
- Identify applications that use iconv with IBM1364, IBM1371, IBM1388, IBM1390, or IBM1399.
- Review monitoring for unexplained CPU-bound hangs in text conversion paths.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-835: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2020-27618 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Medium
- CVSS
- 5.5 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H1.83.6Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
5.5MediumVector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://sourceware.org/bugzilla/show_bug.cgi?id=26224CVE reference
- https://sourceware.org/bugzilla/show_bug.cgi?id=19519#c21CVE reference
- GLSA-202107-07CVE reference · vendor-advisory
- https://www.oracle.com/security-alerts/cpujan2022.htmlCVE reference
- https://security.netapp.com/advisory/ntap-20210401-0006/CVE reference
- https://www.oracle.com/security-alerts/cpuapr2022.htmlCVE reference
- [debian-lts-announce] 20221017 [SECURITY] [DLA 3152-1] glibc security updateCVE reference · mailing-list
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Loop with Unreachable Exit Condition ('Infinite Loop')
Loop with Unreachable Exit Condition ('Infinite Loop') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.