Arch Linux update for tor



| Updated: 2017-12-16
Risk High
Patch available YES
Number of vulnerabilities 4
CVE-ID CVE-2017-8819
CVE-2017-8820
CVE-2017-8822
CVE-2017-8823
CWE-ID CWE-20
CWE-476
CWE-416
Exploitation vector Network
Public exploit N/A
Vulnerable software
Arch Linux
Operating systems & Components / Operating system

Vendor Arch Linux

Security Bulletin

This security bulletin contains information about 4 vulnerabilities.

1) Input validation error

EUVDB-ID: #VU37868

Risk: Medium

CVSSv4.0: 6.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2017-8819

CWE-ID: CWE-20 - Improper input validation

Exploit availability: No

Description

The vulnerability allows a remote non-authenticated attacker to perform a denial of service (DoS) attack.

In Tor before 0.2.5.16, 0.2.6 through 0.2.8 before 0.2.8.17, 0.2.9 before 0.2.9.14, 0.3.0 before 0.3.0.13, and 0.3.1 before 0.3.1.9, the replay-cache protection mechanism is ineffective for v2 onion services, aka TROVE-2017-009. An attacker can send many INTRODUCE2 cells to trigger this issue.

Mitigation

Update the affected package tor to version 0.3.1.9-1.

Vulnerable software versions

Arch Linux: All versions

CPE2.3 External links

https://security.archlinux.org/advisory/ASA-201712-10


Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

2) NULL pointer dereference

EUVDB-ID: #VU31386

Risk: Medium

CVSSv4.0: 4.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2017-8820

CWE-ID: CWE-476 - NULL Pointer Dereference

Exploit availability: No

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to a NULL pointer dereference error. A remote attacker can trigger denial of service conditions via a malformed descriptor, aka TROVE-2017-010.

Mitigation

Update the affected package tor to version 0.3.1.9-1.

Vulnerable software versions

Arch Linux: All versions

CPE2.3 External links

https://security.archlinux.org/advisory/ASA-201712-10


Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

3) Input validation error

EUVDB-ID: #VU37869

Risk: Low

CVSSv4.0: 1.7 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2017-8822

CWE-ID: CWE-20 - Improper input validation

Exploit availability: No

Description

The vulnerability allows a remote non-authenticated attacker to gain access to sensitive information.

In Tor before 0.2.5.16, 0.2.6 through 0.2.8 before 0.2.8.17, 0.2.9 before 0.2.9.14, 0.3.0 before 0.3.0.13, and 0.3.1 before 0.3.1.9, relays (that have incompletely downloaded descriptors) can pick themselves in a circuit path, leading to a degradation of anonymity, aka TROVE-2017-012.

Mitigation

Update the affected package tor to version 0.3.1.9-1.

Vulnerable software versions

Arch Linux: All versions

CPE2.3 External links

https://security.archlinux.org/advisory/ASA-201712-10


Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

4) Use-after-free

EUVDB-ID: #VU31388

Risk: High

CVSSv4.0: 7.2 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2017-8823

CWE-ID: CWE-416 - Use After Free

Exploit availability: No

Description

The vulnerability allows a remote non-authenticated attacker to execute arbitrary code.

In Tor before 0.2.5.16, 0.2.6 through 0.2.8 before 0.2.8.17, 0.2.9 before 0.2.9.14, 0.3.0 before 0.3.0.13, and 0.3.1 before 0.3.1.9, there is a use-after-free in onion service v2 during intro-point expiration because the expiring list is mismanaged in certain error cases, aka TROVE-2017-013.

Mitigation

Update the affected package tor to version 0.3.1.9-1.

Vulnerable software versions

Arch Linux: All versions

CPE2.3 External links

https://security.archlinux.org/advisory/ASA-201712-10


Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.



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