Malicious PDF — malware analysis report

Static analysis result for SHA-256 9943fb4230ebb75a…

MALICIOUS

PDF

74.0 KB Created: 2021-05-26 11:26:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: 91400654206d85796510ef3c52039bca SHA-1: 91afb3b2547ee15bb89b0dfa794fa9eeb10efd17 SHA-256: 9943fb4230ebb75a52f52ca83e56a8dda47e7559f8bceb8ec89166d71bc0e2e8
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • 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://crophysi.ru/strik?utm_term=dibujos+de+dinosaurios+para+colorear+con+nombres PDF link annotation
    • https://pegufalijedosok.weebly.com/uploads/1/3/4/5/134589263/6145072.pdfIn PDF document text
    • https://xisosisudotaju.weebly.com/uploads/1/3/0/7/130738948/4377876.pdfIn PDF document text
    • https://mimedotaxejibi.weebly.com/uploads/1/3/0/8/130873786/vonaralopuf_vinutuzedotevif.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4500904/normal_5ff3f4d5e693f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4377706/normal_602477463b5ef.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4384026/normal_5fe8c539a956e.pdfIn PDF document text
    • https://xubebedi.weebly.com/uploads/1/3/0/7/130776367/viwowemidulex.pdfIn PDF document text
    • https://xefufisemir.weebly.com/uploads/1/3/5/3/135393588/62be757.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4384645/normal_5fea327b487ad.pdfIn PDF document text
    • https://kopaluzakiletal.weebly.com/uploads/1/3/0/7/130739322/510483.pdfIn PDF document text
    • https://nefavegipu.weebly.com/uploads/1/3/4/3/134365482/rapenerixafexo.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/7821d5d9-244b-4bd8-8035-10bfee0e8050/autism_spectrum_disorder_and_enuresis.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2286cd03-ffa3-428e-b0d2-de9968668559/diono_radian_car_seat_installation.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6e76b894-8bd7-454a-8471-a03ae726c9cd/22127930389.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8fe1b77f-bf21-4848-9123-f5c5cf1a37e7/alone_together_escape_room_walkthrough_player_1.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d6f4f373-a236-4532-a1a6-f319c022c90b/fudasavus.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/eba08797-3806-45fd-996b-097110a6e5f6/the_mysterious_benedict_society_and_the_riddle_of_ages_review.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3c4a28f6-a319-4451-858a-78e1c304584c/37411403319.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5091ca6a-272f-4e53-b0fb-da7bf20b3a00/the_mist_stephen_king_chapter_summary.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/224931c6-784d-423d-b94a-2d6e1c346edb/tizijenixirokoz.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e092.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE092 5436 bytes
SHA-256: b9ba439f07eb81f754d95a989a26db3e0e94cb413977ef8e00c74518f45d2822
font_01_sfnt_off0000f2f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2F5 11588 bytes
SHA-256: ae1f3e0eaf624cc92460e699ea0aa201d8c87096461f0bf20d4e07eebaae4f44