Debian update for apache2
| Risk | Medium |
| Patch available | YES |
| Number of vulnerabilities | 5 |
| CVE-ID | CVE-2020-35452 CVE-2021-26690 CVE-2021-26691 CVE-2021-30641 CVE-2021-31618 |
| CWE-ID | CWE-121 CWE-476 CWE-20 |
| Exploitation vector | Network |
| Public exploit | N/A |
| Vulnerable software Subscribe |
apache2 (Debian package) Operating systems & Components / Operating system package or component |
| Vendor | Debian |
Security Bulletin
This security bulletin contains information about 5 vulnerabilities.
1) Stack-based buffer overflow
EUVDB-ID: #VU53775
Risk: Medium
CVSSv3.1: 6.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]
CVE-ID: CVE-2020-35452
CWE-ID:
CWE-121 - Stack-based buffer overflow
Exploit availability: No
DescriptionThe vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to a boundary error when processing Digest nounces in mod_auth_digest. A remote unauthenticated attacker can send a specially crafted HTTP request, trigger stack overflow by one nul byte and crash the server.
Update apache2 package to version 2.4.38-3+deb10u5.
Vulnerable software versionsapache2 (Debian package): 2.4.1-1 - 2.4.46-2
External linkshttp://www.debian.org/security/2021/dsa-4937
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: #VU53777
Risk: Medium
CVSSv3.1: 6.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]
CVE-ID: CVE-2021-26690
CWE-ID:
CWE-476 - NULL Pointer Dereference
Exploit availability: No
DescriptionThe vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to a NULL pointer dereference error in mod_session. A remote attacker can pass specially crafted data to the application and perform a denial of service (DoS) attack.
MitigationUpdate apache2 package to version 2.4.38-3+deb10u5.
Vulnerable software versionsapache2 (Debian package): 2.4.1-1 - 2.4.46-2
External linkshttp://www.debian.org/security/2021/dsa-4937
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) NULL pointer dereference
EUVDB-ID: #VU53776
Risk: Low
CVSSv3.1: 5.2 [CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]
CVE-ID: CVE-2021-26691
CWE-ID:
CWE-476 - NULL Pointer Dereference
Exploit availability: No
DescriptionThe vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to a NULL pointer dereference error in mod_session. A a malicious backend server or SessionHeader can trigger a denial of service (DoS) condition.
MitigationUpdate apache2 package to version 2.4.38-3+deb10u5.
Vulnerable software versionsapache2 (Debian package): 2.4.1-1 - 2.4.46-2
External linkshttp://www.debian.org/security/2021/dsa-4937
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) Input validation error
EUVDB-ID: #VU53774
Risk: Medium
CVSSv3.1: 6.4 [CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N/E:U/RL:O/RC:C]
CVE-ID: CVE-2021-30641
CWE-ID:
CWE-20 - Improper input validation
Exploit availability: No
DescriptionThe vulnerability allows a remote attacker to bypass implemented security restrictions.
The vulnerability exists due to incorrect parsing of Apache configuration files. An unexpected
Update apache2 package to version 2.4.38-3+deb10u5.
Vulnerable software versionsapache2 (Debian package): 2.4.1-1 - 2.4.46-2
External linkshttp://www.debian.org/security/2021/dsa-4937
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.
5) NULL pointer dereference
EUVDB-ID: #VU53773
Risk: Medium
CVSSv3.1: 6.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]
CVE-ID: CVE-2021-31618
CWE-ID:
CWE-476 - NULL Pointer Dereference
Exploit availability: No
DescriptionThe vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to a NULL pointer dereference error in mod_http2 in Apache HTTP server. A remote attacker can send specially crafted request to the server and perform a denial of service (DoS) attack.
MitigationUpdate apache2 package to version 2.4.38-3+deb10u5.
Vulnerable software versionsapache2 (Debian package): 2.4.1-1 - 2.4.46-2
External linkshttp://www.debian.org/security/2021/dsa-4937
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.
