Malicious PDF — malware analysis report

Static analysis result for SHA-256 71dfb00c457b016b…

MALICIOUS

PDF

73.7 KB Created: 2021-06-12 15:49:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: e3163bc3b407b39a0cd131ca85972267 SHA-1: da1b996b027231f45535f0ffb5d938f9c5f861f8 SHA-256: 71dfb00c457b016b011fb7ccaccc85a5e8ff715ce66f0c1cecb3b74a36b640b2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs pointing to compromised WordPress sites and disposable hosting, suggesting it functions as a link farm to distribute phishing or malware. The presence of 'utm_term' parameters in some URLs further supports a phishing or tracking objective.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://cructi.ru/uplcv?utm_term=restart+usb+ubuntu PDF link annotation
    • https://rosemonttherapy.health/wp-content/plugins/super-forms/uploads/php/files/hg9rspc0mg1tu9ed4d68db7ub6/dekoralarovupijavuvoxof.pdfIn PDF document text
    • https://www.jahnigterbraak.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160ac573625bc5---wufuzoxetuzom.pdfIn PDF document text
    • http://yakutiaprime.ru/SITE/files/editor/file/61632372232.pdfIn PDF document text
    • http://sxcec.org/userfiles/file/pumimuxalakojek.pdfIn PDF document text
    • http://ophtalmic-overnight.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16084f1e8ef0fa---32189145815.pdfIn PDF document text
    • https://www.shopveriamici.com/wp-content/plugins/super-forms/uploads/php/files/fs0cmog190g50d8ipmavk8iraf/44823024787.pdfIn PDF document text
    • https://expungemyrecordnj.com/wp-content/plugins/formcraft/file-upload/server/content/files/160735a25af76d---gabotoxusigejalu.pdfIn PDF document text
    • http://cesishotel.lv/res/wysiwyg/file/81038310938.pdfIn PDF document text
    • https://balance-global.com/wp-content/plugins/super-forms/uploads/php/files/gi992d47kut59te1q44s1523nj/75431580661.pdfIn PDF document text
    • https://www.advids.co/wp-content/plugins/formcraft/file-upload/server/content/files/160acf2038ea15---razorizenoroxalej.pdfIn PDF document text
    • https://www.officinadelgustoroma.com/wp-content/plugins/super-forms/uploads/php/files/8b328434a8935a79e053d5fb1ad67dc8/96636807730.pdfIn PDF document text
    • https://poolpoint.be/uploads/file/91419560587.pdfIn PDF document text
    • https://www.ideakliniksisli.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e07d69cd06---10275429390.pdfIn PDF document text
    • https://vickers-electronics.co.uk/wp-content/plugins/super-forms/uploads/php/files/209b81a79ea86e41e021e708977c86dc/74249899013.pdfIn PDF document text
    • https://www.andeanskyline.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad6691620aa---32282227097.pdfIn PDF document text
    • https://www.golddustdental.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e5de90ad3a---katapaxejutuxur.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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_off0000e1b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1B0 4796 bytes
SHA-256: ae145cfefa2544d9bed128f85e7d93508d61afc4de745888e687646a565d02ca
font_01_sfnt_off0000f20f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF20F 11648 bytes
SHA-256: 276cff814bbc3da8f3605ad63c1351fe1a4eb983298122597ae6fc14c438a956