GIMP app/xcf/xcf-load.c xcf_load_layer_props use after free

CVSS Meta Temp Score
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CTI Interest Score
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7.6$0-$5k0.00

Summaryinfo

A vulnerability was found in GIMP. It has been declared as critical. This affects the function xcf_load_layer_props of the file app/xcf/xcf-load.c. The manipulation results in use after free. This vulnerability was named CVE-2016-4994. The attack needs to be approached locally. There is no available exploit. It is advisable to implement a patch to correct this issue.

Detailsinfo

A vulnerability classified as critical has been found in GIMP (Image Processing Software) (version now known). Affected is the function xcf_load_layer_props of the file app/xcf/xcf-load.c. The manipulation with an unknown input leads to a use after free vulnerability. CWE is classifying the issue as CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

Use-after-free vulnerability in the xcf_load_image function in app/xcf/xcf-load.c in GIMP allows remote attackers to cause a denial of service (program crash) or possibly execute arbitrary code via a crafted XCF file.

The weakness was presented 06/22/2016 as confirmed git commit (GIT Repository). The advisory is shared for download at git.gnome.org. The public release was coordinated in cooperation with the vendor. This vulnerability is traded as CVE-2016-4994 since 05/24/2016. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. Successful exploitation requires user interaction by the victim. There are known technical details, but no exploit is available. The advisory points out:

The properties PROP_ACTIVE_LAYER, PROP_FLOATING_SELECTION, PROP_ACTIVE_CHANNEL saves the current object pointer the @info structure. Others like PROP_SELECTION (for channel) and PROP_GROUP_ITEM (for layer) will delete the current object and create a new object, leaving the pointers in @info invalid (dangling). Therefore, if a property from the first type will come before the second, the result will be an UaF in the last lines of xcf_load_image (when it actually using the pointers from @info).

The vulnerability scanner Nessus provides a plugin with the ID 91831 (Debian DLA-525-1 : gimp security update), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Debian Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 256091 (CentOS Security Update for gimp-help (CESA-2016:2589)). The advisory illustrates:

I wasn't able to exploit this bug because that g_object_instance->c_class gets cleared by the last g_object_unref and GIMP_IS_{LAYER,CHANNEL} detects that and return FALSE.

Applying a patch is able to eliminate this problem. The bugfix is ready for download at git.gnome.org. A possible mitigation has been published immediately after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Tenable (91831), SecurityFocus (BID 91425†) and SecurityTracker (ID 1036226†). Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

Name

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.8
VulDB Meta Temp Score: 7.6

VulDB Base Score: 7.8
VulDB Temp Score: 7.5
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.8
NVD Vector: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Use after free
CWE: CWE-416 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 91831
Nessus Name: Debian DLA-525-1 : gimp security update
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 66585
OpenVAS Name: Fedora Update for gimp FEDORA-2016-20db5e796b
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Patch
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
Exposure Time: 🔍

Patch: git.gnome.org

Timelineinfo

05/24/2016 🔍
06/20/2016 +27 days 🔍
06/22/2016 +2 days 🔍
06/22/2016 +0 days 🔍
06/27/2016 +5 days 🔍
07/06/2016 +9 days 🔍
07/06/2016 +0 days 🔍
07/12/2016 +6 days 🔍
09/29/2024 +3000 days 🔍

Sourcesinfo

Advisory: USN-3025-1
Status: Confirmed
Confirmation: 🔍
Coordinated: 🔍

CVE: CVE-2016-4994 (🔍)
GCVE (CVE): GCVE-0-2016-4994
GCVE (VulDB): GCVE-100-88668

OVAL: 🔍

SecurityFocus: 91425 - GIMP 'app/xcf/xcf-load.c' Multiple Remote Code Execution Vulnerabilities
SecurityTracker: 1036226

Entryinfo

Created: 07/06/2016 09:55
Updated: 09/29/2024 00:50
Changes: 07/06/2016 09:55 (71), 02/16/2019 15:30 (13), 08/26/2022 15:25 (3), 08/26/2022 15:31 (1), 09/29/2024 00:50 (16)
Complete: 🔍
Cache ID: 216::103

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