Malicious PDF — malware analysis report

Static analysis result for SHA-256 31146bc884d40e26…

MALICIOUS

PDF

85.6 KB Created: 2021-03-09 15:25:31 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-18
MD5: 521dd4260d8562deb4fcb2c157f6b08f SHA-1: 9d76d1ffdda5b80fbfb4d52cde69173823e43c4a SHA-256: 31146bc884d40e26506c3e411e00e4bc8933e69d710701cd2448c234e068fac2
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 0.9950

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://xajibur.ru/strik?utm_term=divine+intimacy+calendar+2018 PDF link annotation
    • https://mujilaku.weebly.com/uploads/1/3/4/3/134389228/5540193.pdfIn PDF document text
    • https://kujarubokaja.weebly.com/uploads/1/3/4/5/134590089/9683225.pdfIn PDF document text
    • http://bigijawiv.scienceontheweb.net/bradley_smoker_beef_ribs_recipe.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4446170/normal_5ff6a710e5fb8.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4453909/normal_601ee2c5e93c9.pdfIn PDF document text
    • http://50offshop.pro/truecaller_pro_apk_freer5phd.pdfIn PDF document text
    • http://mmamba.ru/32283637812syq05.pdfIn PDF document text
    • http://beritox.medianewsonline.com/addy_osmani_javascript_design_patterns.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4459188/normal_5fcb1213bc263.pdfIn PDF document text
    • https://xekigumi.weebly.com/uploads/1/3/0/7/130776031/5960572.pdfIn PDF document text
    • http://apelsins.space/652028213094tiq0.pdfIn PDF document text
    • http://capridigi.com/nobapagipkjl8j.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4486975/normal_6037f33e35f5f.pdfIn PDF document text
    • http://nurigoluda.mygamesonline.org/totuginolodigufurave.pdfIn PDF document text
    • https://lanulizuxuja.weebly.com/uploads/1/3/4/6/134658029/4796688.pdfIn PDF document text
    • http://pubggaming.online/free_engagement_invitation_templates_for_wordsmikc.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://nufiwimuzobo.onlinewebshop.net/votibubapudodoxonu.pdfIn PDF document text
    • https://s3.amazonaws.com/wazotojemov/the_school_for_good_and_evil_book_1_read_online.pdfIn PDF document text
    • https://0298dc5a-7924-4276-8279-06452a5288da.filesusr.com/ugd/b30cf0_8ace76c799164d7183be116ca829cfd2.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/farowug/conair_1500w_garment_steamer_gs28_reviews.pdfIn PDF document text
    • https://83d7d1d1-3661-4158-a2cc-78aa4aa39d08.filesusr.com/ugd/163759_82fb8f80636d491bbf8803d56a4fda4f.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/gofiguj/tukebureputinumafokol.pdfIn PDF document text
    • https://ac4cd5cf-e861-4b1b-a585-e47049f737a6.filesusr.com/ugd/843280_16a3f2ee7a95497d8d075e4ffb8e19ca.pdf?index=trueIn PDF document text
    • http://sujawokasafu.onlinewebshop.net/80343055074.pdfIn PDF document text
    • https://eb62986f-0112-409a-9ebe-777412bc5c19.filesusr.com/ugd/26938b_25d570c047c34597be399b626deaf229.pdf?index=trueIn PDF document text
    • https://14319df0-7947-4f0d-bbb3-eaa17d5eb23e.filesusr.com/ugd/c45f38_27b2bab360884a6994b8764303bf5b70.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/tarizirefevifab/dadalupixezorosova.pdfIn PDF document text
    • https://s3.amazonaws.com/dobikasukavu/43730627314.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000fa13.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA13 5588 bytes
SHA-256: 26650b8c4f94bf8a1017581e9b559078fc89dad50c846437e0e9470e885a2827
font_01_sfnt_off00010d0b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D0B 11524 bytes
SHA-256: 028ea4f880805bb335220317e59c6c2505bdefcb1c91452a2e1284aa3b227f8f
font_02_sfnt_off0001330e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1330E 16288 bytes
SHA-256: d44a4bb3f7eaf08118ed439fd46f9c091de4450d98d1f82a3111706ffd5ecbe9