Malicious PDF — malware analysis report

Static analysis result for SHA-256 90cb29f8c32e9e1d…

MALICIOUS

PDF

79.1 KB Created: 2021-09-16 23:01:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 20b8ab3adc8600742e5a83770a26a72d SHA-1: c2eca9b179536830f31171f2245968515994933a SHA-256: 90cb29f8c32e9e1d064e1bb525ab7a83dcf8076ca05e66c548ac5353272ca424
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file is identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Numerous heuristics point to the document being a link farm, with many external URIs hosted on potentially compromised or disposable domains. The presence of multiple PDF link farm indicators suggests a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9958

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://chcial.ru/uplcv?utm_term=word+print+to+pdf+with+hyperlinks PDF link annotation
    • https://leganordavigliana.com/uploads/file/zunixewijof.pdfIn PDF document text
    • http://creativetechno.in/userfiles/file/vabiki.pdfIn PDF document text
    • https://waelfawzy.com/userfiles/file/In PDF document text
    • https://noelex22.org/userfiles/file/rofedo.pdfIn PDF document text
    • http://www.southforconstruction.com/frontend/web/ckfinder/userfiles/files/48466692451.pdfIn PDF document text
    • http://nasfthr.com/userfiles/file/jidisowinabe.pdfIn PDF document text
    • http://elandtour.com/FileData/ckfinder/files/20210911_92363EE9144B5108.pdfIn PDF document text
    • http://www.champcaregivers.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130ccee792e3---7682276274.pdfIn PDF document text
    • https://www.capitalroofingct.com/wp-content/plugins/formcraft/file-upload/server/content/files/161389866c3641---xizigizazadevaxuxuzuru.pdfIn PDF document text
    • http://intertermo.nl/userfiles/file/nuzufozonoradiwal.pdfIn PDF document text
    • https://www.indee-r.fr/wp-content/plugins/super-forms/uploads/php/files/3a28b8c2534f068d5ded8fbe4bcf7e6b/22410177529.pdfIn PDF document text
    • http://chugguwang.com/files/fckeditor/file/28392073273.pdfIn PDF document text
    • http://chuanghuilaw.com/filespath/files/20210914075902.pdfIn PDF document text
    • https://hijaustabilo.com/contents/files/63962925416.pdfIn PDF document text
    • http://duplisite.com/userfiles/file/50770817485.pdfIn PDF document text
    • https://olamare.com/img/uploaded/file/32562918859.pdfIn PDF document text
    • http://kant21.com/userData/board/file/63220955760.pdfIn PDF document text
    • https://drbumbnursinghome.in/ckfinder/userfiles/files/dipowezaserujiviguduwu.pdfIn PDF document text
    • https://unitjaya.com/contents/files/75626192041.pdfIn PDF document text
    • http://www.fsnn.se/wp-content/plugins/formcraft/file-upload/server/content/files/16132d3d1928e3---xanixuwunezadikonake.pdfIn PDF document text
    • http://kowalstwwo.pl/public/cms/images/file/kowolofasodikabisanesev.pdfIn PDF document text
    • http://surmounttravel.com/userfiles/files/megesubegoma.pdfIn PDF document text
    • https://lsv-wittlage.de/ckfinder/userfiles/files/53610987509.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://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_off0000d0d9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0D9 10720 bytes
SHA-256: c27c812ecf9fc5d5cf75e9697d0037fd719ebbb3b48ab05e74d4920f07be08b3
font_01_sfnt_off0000e972.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE972 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010184.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10184 17636 bytes
SHA-256: 76926f7051f9a1739bbf9aeea559548b3955b2cc14df3264b2b65cc1d3dddc9e