Adobe Flash Player Use-After-Free
CVE-2015-5123 is a critical-severity use after free vulnerability in Enterprise Linux Desktop from Red Hat, with a CVSS 3.1 base score of 9.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected Enterprise Linux Desktop versions: 5.0; 6.0. The record does not name a fixed version, so check the vendor advisory. CISA added it to the Known Exploited Vulnerabilities catalogue on April 13, 2022, which means attacks have been observed in the wild.
Attackers are already exploiting this vulnerability, according to CISA.
What to do
- Check which version of Enterprise Linux Desktop you run against the affected versions below, and install the vendor's latest release.
- CISA's required action: The impacted product is end-of-life and should be disconnected if still in use.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Red Hat | Enterprise Linux Desktop | 5.0; 6.0 | Not stated |
| Red Hat | Enterprise Linux Server | 5.0; 6.0 | Not stated |
| Red Hat | Enterprise Linux Server EUS | 6.6 | Not stated |
| Red Hat | Enterprise Linux Workstation | 5.0; 6.0 | Not stated |
| openSUSE | Evergreen | 11.4 | Not stated |
| SUSE | Linux Enterprise Desktop | 11; 12 | Not stated |
| SUSE | Linux Enterprise Workstation Extension | 12 | Not stated |
| Adobe | Flash Player | 11.0 through 11.2.202.481; 13.0 through 13.0.0.302; 18.0 through 18.0.0.203 | Not stated |
| Adobe | Flash Player Desktop Runtime | 18.0 through 18.0.0.203 | Not stated |
Version data comes from NVD's product matching. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- 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
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 9.8 | Critical | NVD |
| CVSS 3.1 | 7.8 | High | CISA (ADP) |
| CVSS 2.0 | 10.0 | High | NVD |
Official description
Use-after-free vulnerability in the BitmapData class in the ActionScript 3 (AS3) implementation in Adobe Flash Player 13.x through 13.0.0.302 on Windows and OS X, 14.x through 18.0.0.203 on Windows and OS X, 11.x through 11.2.202.481 on Linux, and 12.x through 18.0.0.204 on Linux Chrome installations allows remote attackers to execute arbitrary code or cause a denial of service (memory corruption) via crafted Flash content that overrides a valueOf function, as exploited in the wild in July 2015.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Use After Free
The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory belongs to the code that operates on the new pointer.
How developers prevent this class of flaw
- Choose a language that provides automatic memory management.
- When freeing pointers, be sure to set them to NULL once they are freed. However, the utilization of multiple or complex data structures may lower the usefulness of this strategy.
Timeline
- CVE record published.
- Added to CISA's Known Exploited Vulnerabilities catalogue.
- Deadline for US federal agencies to remediate, set by CISA.
- CISA published its SSVC assessment (exploitation: active, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Third-party and government advisories
- lists.opensuse.org/opensuse-security-announce/2015-07/msg00028.htmlMailing List, Third Party Advisory
- lists.opensuse.org/opensuse-security-announce/2015-07/msg00029.htmlMailing List, Third Party Advisory
- lists.opensuse.org/opensuse-security-announce/2015-07/msg00032.htmlMailing List, Third Party Advisory
- marc.info/?l=bugtraq&m=144050155601375&w=2Mailing List, Third Party Advisory
- rhn.redhat.com/errata/RHSA-2015-1235.htmlThird Party Advisory
- kb.cert.org/vuls/id/918568Third Party Advisory, US Government Resource
- us-cert.gov/ncas/alerts/TA15-195AThird Party Advisory, US Government Resource
- security.gentoo.org/glsa/201508-01Third Party Advisory
- cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2015-5123US Government Resource
Other references
- github.com/cisagov/vulnrichment/issues/196Issue Tracking
Other vulnerabilities in Enterprise Linux Desktop
- 7.8 High severity
Linux Kernel Use-After-Free Exploited
- 7.8 High severity
- 9.8 Critical severity
- 8.8 High severity
- 7.8 High severity
- 7.8 High severity
Recent Use After Free vulnerabilities
- 9.8 Critical severity
Adobe Flash Player Use-After-Free Exploited
- 9.8 Critical severity
Adobe Flash Player Use-After-Free Exploited
- 9.8 Critical severity
Adobe Flash Player Use-After-Free Exploited
- 10.0 High severity
- 8.8 High severity
- 10.0 High severity
Adobe Reader and Acrobat Use-After-Free Exploited
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