Malicious PDF — malware analysis report

Static analysis result for SHA-256 90c5a4604e35094f…

MALICIOUS

PDF

75.9 KB Created: 2021-03-05 10:32:12 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: 152a682be25c1ae4ef89942c7f856597 SHA-1: 13166aa69538bf0bf0f3db25b6a6a54bff5b5181 SHA-256: 90c5a4604e35094f5361b38c85eec586ec4653a5fab697dd2fcb05ef7f617b8d
226 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious File T1059.007 JavaScript

This PDF document was flagged as malicious by ClamAV and an ML classifier. It uses a remote-support lure. 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 0.9993

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Remote-support tool lure high SE_REMOTE_SUPPORT_LURE
    Document instructs the user to install, open, or connect with a remote-support tool such as AnyDesk, TeamViewer, Quick Assist, or ScreenConnect — high-risk in an unsolicited document
  • 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://dugedepap.ru/wix?keyword=building+a+switch+and+router+network+6.5.1.2 PDF link annotation
    • https://cdn.sqhk.co/zovitamojim/v6Rgf3c/great_little_war_game_free.pdfIn PDF document text
    • http://kmikaerfs.ru/6005628985915g9h.pdfIn PDF document text
    • http://svoytrylend.xyz/burdwan_university_distance_b._ed_application_formtj0p6.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4489977/normal_5fdba1ffde210.pdfIn PDF document text
    • https://rofaxebawo.weebly.com/uploads/1/3/4/7/134750080/kupibawedob.pdfIn PDF document text
    • https://cdn.sqhk.co/mizogujuzo/EvPhfTh/30839252130.pdfIn PDF document text
    • https://cdn.sqhk.co/towevefizub/jJjdGSH/kisedovijenagaloru.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4370059/normal_6016c7d833dd9.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4390385/normal_5fda841e5df15.pdfIn PDF document text
    • https://cdn.sqhk.co/jobubexivex/V0hcEig/34509726782.pdfIn PDF document text
    • http://unityfree.xyz/53114624385szubi.pdfIn PDF document text
    • http://piredvizhnik.com/71803378348hji0t.pdfIn PDF document text
    • https://cdn.sqhk.co/jotapepikota/gjhQgrT/xiragibezoxunor.pdfIn PDF document text
    • http://vamoktin.ru/ulcerative_colitis_treatment_guidelines_canadal3yfp.pdfIn PDF document text
    • https://cdn.sqhk.co/lodikorep/aaijgek/79820189286.pdfIn PDF document text
    • https://bukodebavuv.weebly.com/uploads/1/3/4/6/134657655/5625408.pdfIn PDF document text
    • https://tedozumezefa.weebly.com/uploads/1/3/2/7/132740670/famisagetare-foberuziw.pdfIn PDF document text
    • https://cdn.sqhk.co/rasepotobami/agtiqQT/pemexiveseb.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/mafavuzenoliki/33138677365.pdfIn PDF document text
    • https://s3.amazonaws.com/rodakarugupoko/78838339149.pdfIn PDF document text
    • https://s3.amazonaws.com/wurivuve/96104144914.pdfIn PDF document text
    • https://s3.amazonaws.com/xirixepo/guided_canyoneering_in_moab_utah.pdfIn PDF document text
    • https://s3.amazonaws.com/xujitezu/hx_stomp_vs_pedals.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_off0000ec00.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC00 5900 bytes
SHA-256: 19ebac51c9870dd0df10fa29d8a557425347b0056fbff202e162f52a1fc0e66c
font_01_sfnt_off00010032.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10032 9936 bytes
SHA-256: 59c0a7b8873939b20e4fb32c8c8b6e842a4ed75b12b8cf2397c6e289af37488e