Malicious PDF — malware analysis report

Static analysis result for SHA-256 a281cbe3a362de52…

MALICIOUS

PDF

72.8 KB Created: 2021-06-14 07:49:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-13
MD5: 1f30949402a996f5ba5643f60456b6cd SHA-1: 7127dc1a278b9d2d6d56fd8290c6682adc7527a0 SHA-256: a281cbe3a362de527a3fa991975bc696ec2fdc64bf49110ec756140003832d00
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many of which point to disposable hosting or are used in a link farm strategy, as indicated by the PDF_SEO_LINK_FARM and PDF_SEO_DISPOSABLE_LINK_FARM heuristics. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a spearphishing attachment used to lure users to malicious sites.

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://archism.ru/pbw?utm_term=proprietor+balance+sheet+format PDF link annotation
    • https://subefivu.weebly.com/uploads/1/3/4/6/134688636/a5130f103.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4450257/normal_600fb80977111.pdfIn PDF document text
    • https://rixifumalig.weebly.com/uploads/1/3/1/4/131437092/kebezosu.pdfIn PDF document text
    • https://fenawivo.weebly.com/uploads/1/3/4/0/134000055/mipumesadogizo-detodu.pdfIn PDF document text
    • https://wapexuji.weebly.com/uploads/1/3/5/3/135329723/1e44a.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4426090/normal_602e09c9a0bd7.pdfIn PDF document text
    • https://mezonojasu.weebly.com/uploads/1/3/4/6/134639114/nukapi.pdfIn PDF document text
    • https://gobumireg.weebly.com/uploads/1/3/1/3/131383916/xibapufalulaxe.pdfIn PDF document text
    • https://zalivibutadugaf.weebly.com/uploads/1/3/5/3/135391941/172fcbd093d4c37.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4370088/normal_5fdbc44bc546d.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://bobiginokemo.pbworks.com/w/file/fetch/144983121/kiwi_vpn_premium_mod_apk.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/430282e0-5cc6-4c80-b01e-3f807fc48a8b/palme_yaynlar_11_snf_biyoloji_soru_bankas_zmleri.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/46014377-76de-4971-9296-d2585d7be1b3/how_to_find_distance_from_displacement.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d05f3a68-4ace-411f-b035-9f09a7b4f4d7/gimp_drawing_tutorial_for_beginners.pdfIn PDF document text
    • http://tujelupirobe.pbworks.com/w/file/fetch/145174962/4udrama_meteor_garden_ep_1.pdfIn PDF document text
    • http://sonubugu.pbworks.com/f/turkey_scholarship_interview_questions.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2e16505e-5768-4355-ba09-2faf8eeb305c/bruins_blue_jackets_score_today.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a08ed163-beaf-46f1-bbfd-1cc4e911d418/did_the_actor_who_played_hagrid_in_harry_potter_die.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ce3193f6-2527-4a91-94a4-21137390e79c/52173193733.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b7528d27-f729-4d73-9528-f09e5fcecda5/ps4_gold_headset_user_manual.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/59cb5433-b938-40de-aff9-7c8d09fc07b9/watibudimiguwazuw.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_off0000dfec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFEC 5396 bytes
SHA-256: 3f99fbe95bbe6a2ba8e7f6ea4d5ceebd3a1f1dc1bc7a6e990b49ea2992d45484
font_01_sfnt_off0000f217.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF217 10696 bytes
SHA-256: b40c636a9944cb69f572252fc45b2cfc831e30e2909abf65e15d5fc34c063ea4