Malicious PDF — malware analysis report

Static analysis result for SHA-256 526a01589942010b…

MALICIOUS

PDF

82.6 KB Created: 2021-09-03 02:20:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 26ce957f7d64191f3e6ccd777174899d SHA-1: fd57c7b06232d9349ea1658c843024115f44edd8 SHA-256: 526a01589942010bb8f142d6943dfac18ea8ed54177a6db1422c95e786f4b005
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. Heuristics identified it as a PDF link farm pointing to numerous domains, some of which are hosted on compromised WordPress sites or appear to be disposable. The presence of 'utm_term' in URLs suggests an attempt to track user interactions, common in phishing or scam campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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://queure.ru/uplcv?utm_term=scubapro+mk25+repair+manual PDF link annotation
    • http://atrsara.ir/resource/files/54081450869.pdfIn PDF document text
    • http://ageddfjtjgrade.pretty-match.com/upload/files/pijinivabeseborine.pdfIn PDF document text
    • http://gancza.pl/userfiles/file/78707379963.pdfIn PDF document text
    • http://learnazia.com/fck/imagesfile/nizeluwezuxumiz.pdfIn PDF document text
    • http://www.carolglassman.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612b59440e552---84754043043.pdfIn PDF document text
    • http://svs-pm.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac5bf847e54---sobego.pdfIn PDF document text
    • http://gowowdeli.com/uploads/files/935616171.pdfIn PDF document text
    • http://eco-versute.com/app/webroot/ckfinder/userfiles/files/97060440163.pdfIn PDF document text
    • http://skuplaptop.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16072b95ba87aa---88504779097.pdfIn PDF document text
    • http://valsadindustries.com/userfiles/file/60603554367.pdfIn PDF document text
    • https://feldmann-spedition.de/pics/userfiles/file/navelipep.pdfIn PDF document text
    • http://hattrick-sports.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c86a0b77594---22580803419.pdfIn PDF document text
    • http://nkland.org/userfiles/files/90473178829.pdfIn PDF document text
    • http://htwy.com/upload/file/gugasut.pdfIn PDF document text
    • http://sattamatkapatti.com/userfiles/file/renezagawatax.pdfIn PDF document text
    • http://pho32shabu.com/uploads/files/98066974354.pdfIn PDF document text
    • https://diarch.in/WYSIWYGImage/file/pavuwufejiz.pdfIn PDF document text
    • http://vhz.cz/user-files/32553738908.pdfIn PDF document text
    • http://www.hgbehringer.de/img/files/files/dadotategifagazifire.pdfIn PDF document text
    • http://bhartiyambeohari.in/userfiles/file/91580617828.pdfIn PDF document text
    • https://apronorte.org.br/ckfinder/userfiles/files/motimem.pdfIn PDF document text
    • http://togclick.com/media/userFckfiles/file/kufadazifurixusof.pdfIn PDF document text
    • http://geodez.com/pliki/file/71469811502.pdfIn PDF document text
    • http://kahsport.cz/userfiles/file/83892220623.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_off0000d82e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD82E 19836 bytes
SHA-256: 776726e961f88d818c86c68a00982bcaa4add08045a7414af07e665000e067f9
font_01_sfnt_off00010bee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BEE 10932 bytes
SHA-256: 921731d632579a58679d4f8780311d6abed201e1058860c4db95d1fe6e477d0d
font_02_sfnt_off00012510.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12510 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1