Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf84a5f7fbd9ca4a…

MALICIOUS

PDF

69.4 KB Created: 2020-11-11 07:56:23 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: c38f7e819ce1aa18dcbd2120ea76c628 SHA-1: 133f1dc3a96e1b203a1181ea43c9730b6104097a SHA-256: cf84a5f7fbd9ca4a1dba366c5efd81da76b8a8e09a57e220f92abb9e7d702f4b
214 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple embedded links, with one specifically pointing to known malicious redirector infrastructure. The ML classifier and ClamAV detection strongly indicate malicious intent. The presence of a link farm suggests an attempt to distribute or redirect to other malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 5

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://traffmen.ru/123?keyword=psu+academic+calendar+2021
    • https://taroxeme.weebly.com/uploads/1/3/4/3/134358537/xajixilulas.pdf
    • https://juragubiv.weebly.com/uploads/1/3/0/8/130874328/velukuziralijomem.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/c49d8f6b-afaf-4ffc-ba71-86e42b7b09da/mavajorejolofulax.pdf
    • https://uploads.strikinglycdn.com/files/991896d0-d7a4-4d5b-8e23-370ab8e84da0/69262313212.pdf
    • https://uploads.strikinglycdn.com/files/ee1611a9-a9de-48c1-8077-80425a152573/kikuzowanumex.pdf
    • https://uploads.strikinglycdn.com/files/02ce4402-3381-4eb0-ba94-1e97a416df4f/hotmail_login_problem_redirect.pdf
    • https://uploads.strikinglycdn.com/files/506fbaba-cdbe-4805-8b5a-6a7d81ee37cf/sm64_rom_hacks_list.pdf
    • https://uploads.strikinglycdn.com/files/3028b241-ab57-4a55-b988-aabcd6eb47bd/81764385266.pdf
    • https://uploads.strikinglycdn.com/files/37c32ba9-863c-4f98-804c-77d0039e560a/a_practical_guide_to_linux_sobell.pdf
    • https://uploads.strikinglycdn.com/files/85442f30-87dd-4ba4-8478-f34eb03e46c8/14481378098.pdf
    • https://uploads.strikinglycdn.com/files/c6c69501-e85d-4637-8d85-d21df9a17560/alan_bryman_social_research_methods.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d188.bin
4e8ab490c7bf7679382872154478248345d00c6e95601acec46360f863b434c4
pdf-font-stream PDF embedded font (sfnt) at offset 0xD188 5412 bytes
font_01_sfnt_off0000e3dc.bin
8600ee2449f24c8ba6db55468feea60825f3af50d0e8322492186f3f42a3f22e
pdf-font-stream PDF embedded font (sfnt) at offset 0xE3DC 10960 bytes