Malicious PDF — malware analysis report

Static analysis result for SHA-256 a595e877f0d4d4e5…

MALICIOUS

PDF

76.6 KB Created: 2021-04-05 11:01:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-10
MD5: d5b0452e573ffc1bedc6b7f3a39edf88 SHA-1: 608be1e126d3b25294176447bc8f1b896a94c674 SHA-256: a595e877f0d4d4e54d0b2c1df16e2a6e95a59312242d30fb6efb084708429b11
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 pointing to disposable hosting, indicating a link farm or SEO spam operation. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution via these links. No scripts were extracted, but the PDF structure itself is indicative of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://pelibifir.ru/wix?keyword=ultimate+sheet+metal+fabrication+book+pdf PDF link annotation
    • https://cdn.sqhk.co/rutisifelom/dto8tjf/20314926372.pdfIn PDF document text
    • http://dubotivuga.22web.org/ecocardiografia_tridimensional.pdfIn PDF document text
    • http://timelessdecorum.com/hp_4500_print_cartridge_problem_tri_color3cp4k.pdfIn PDF document text
    • http://nosinoski.shop/sofewumezagadelipijugs08g.pdfIn PDF document text
    • https://cdn.sqhk.co/nuroteditu/iighhic/entergy_new_orleans_customer_service_phone_number.pdfIn PDF document text
    • https://cdn.sqhk.co/manuguwe/ZM69ii3/sea_battle_iphone_how_to_play.pdfIn PDF document text
    • https://cdn.sqhk.co/kumotuxijufu/jeaGjeN/numberblocks_hide_and_seek_gameplay.pdfIn PDF document text
    • http://repair-kompov.ru/13035952394z49jh.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/a4b2ac8d-8a1f-4142-a10d-b5f9e9d98c09/environmental_impact_assessment_format.pdfIn PDF document text
    • https://s3.amazonaws.com/xuzed/lejolijopesujapaxanemegag.pdfIn PDF document text
    • http://gosigugul.epizy.com/takokidari.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0a85da75-0d9a-4e02-814f-d0c2b49e7b57/what_are_female_saint_names.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/75cbd25d-3808-4634-ba28-f0c933747ad2/shark_lift_away_true_pet_reviews.pdfIn PDF document text
    • https://8ac5c8e1-9174-427d-95c2-90bebb9f105a.filesusr.com/ugd/44b221_e9c7f5dcc31a469eb0175cbf0e1ff8a3.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/tarizirefevifab/6332179787.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7ef7c71f-b948-452d-84b5-f14356744d1a/john_deere_lawn_mower_wheel_weights.pdfIn PDF document text
    • https://s3.amazonaws.com/ponivotigegepub/a_discovery_of_witches_cast.pdfIn PDF document text
    • https://s3.amazonaws.com/padosumifubobo/wixanuzesaditewewimoxugu.pdfIn PDF document text
    • http://nupudanotagudot.rf.gd/how_to_move_pages_in_adobe_acrobat_pro.pdfIn PDF document text
    • https://s3.amazonaws.com/zarusegibitumet/elgato_video_capture.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b6ac3ebb-f7e7-4867-b516-fe49f65ae512/mirimilun.pdfIn PDF document text
    • https://b354d503-40d1-4c97-84b4-bc0b16c12f35.filesusr.com/ugd/8c7d07_efa20d8430004e1ea4f1c63706120a6a.pdf?index=trueIn PDF document text
    • https://79e8b926-cc52-4cef-90ae-68e3990d752e.filesusr.com/ugd/694d5d_5567830f47554874ad16a2eaf43616e6.pdf?index=trueIn 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_off0000ed67.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED67 5592 bytes
SHA-256: 4ba09f77e1ed565035acfa127e51aada4ed8770bba97eb1630b9a2681154719e
font_01_sfnt_off00010038.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10038 10572 bytes
SHA-256: 573514040ff1967b1d2e7fcdeff5c5b3c042296c9cfd1b42ca488269064470bc