Malicious PDF — malware analysis report

Static analysis result for SHA-256 b105b5e53fb2a6c8…

MALICIOUS

PDF

102.5 KB Created: 2021-04-06 18:21:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: bd5e84acdb44302d37f1e8f61f559206 SHA-1: 7820ef288c11f1de158265cc8fa4b9d1ac698f81 SHA-256: b105b5e53fb2a6c81d58e756a1a2bf42ba6b59b8fd0f838018baec67722952e9
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, a technique often used to redirect users to malicious websites for phishing or malware delivery. The heuristic PDF_SEO_LINK_FARM indicates a large number of such links, and one specific URL, https://pelibifir.ru/award?keyword=dubai+expo+2020+logo+pdf, is directly associated with the document's apparent lure. While no scripts were explicitly extracted, the presence of embedded PDF objects and the ML classifier's high confidence score suggest malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

Heuristics 5

  • 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
  • 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://pelibifir.ru/award?keyword=dubai+expo+2020+logo+pdf
    • http://xiguzot.22web.org/social_entrepreneurship_lecture_notes.pdf
    • https://cdn.sqhk.co/vamunidibu/bhdhI1d/drivetime_houston_tx_southwest_freeway.pdf
    • https://cdn.sqhk.co/vedimofaw/eVHhcja/kijulaweguweburesizeza.pdf
    • https://gonuvogizup.weebly.com/uploads/1/3/1/8/131857562/cae48754.pdf
    • https://cdn.sqhk.co/vugomupuzisa/cKgjKhe/need_for_speed_racing_mod_apk.pdf
    • https://cdn.sqhk.co/fivukidado/PjcqPpi/5597956810.pdf
    • http://sudedelanefozuk.66ghz.com/ks3_maths_solving_equations_worksheet.pdf
    • https://satataro.weebly.com/uploads/1/3/5/3/135350270/7038800.pdf
    • http://ketezudum.22web.org/android_tv_box_user_manual_1._3.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/d1897934-7c75-4dcb-b3c5-e245f8b26bef/jupefazobabiverivexuj.pdf
    • http://tekawuker.epizy.com/geometric_series_test.pdf
    • https://uploads.strikinglycdn.com/files/a3b3656a-94f3-44cb-a8f2-e4e1ce437d7d/juvusubeziximimana.pdf
    • http://luwusifijusu.rf.gd/1900781989.pdf
    • https://uploads.strikinglycdn.com/files/14dd0510-d463-4f4b-b687-32e139b1bbf1/55382883584.pdf
    • https://uploads.strikinglycdn.com/files/60525b1a-2de1-4211-99be-265b55ed933e/classical_guitar_notes_for_beginners.pdf
    • https://uploads.strikinglycdn.com/files/31bd3783-4b53-417a-bd57-2aa252e23942/99096706353.pdf
    • http://nelenubo.rf.gd/vector_checklist_template.pdf
    • http://kodireso.epizy.com/binufom.pdf
    • https://uploads.strikinglycdn.com/files/10b4d470-2e81-495c-8af1-edfedd9ee923/40_rules_of_love.pdf
    • http://fujatelet.epizy.com/derusifufepej.pdf
    • http://demosegepare.rf.gd/29862779266.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://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License
    • http://scripts.sil.org/OFL

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_005_off00016be9.bin
e59980ad52cf04e86cf706f4025540bf174c6d5f455c8d4e923ea2ff019d6509
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x16BE9 19788 bytes
font_00_sfnt_off00012f44.bin
7106b41790a47ecbbbabc6a747eb05eff46684eeffe458ee94494bd58b1ad6b2
pdf-font-stream PDF embedded font (sfnt) at offset 0x12F44 5416 bytes
font_01_sfnt_off000141d7.bin
822ae47927e8878ccf6b379c9974dbc5d354d5785642b30373c5214da700de45
pdf-font-stream PDF embedded font (sfnt) at offset 0x141D7 12964 bytes