Malicious PDF — malware analysis report

Static analysis result for SHA-256 a2c0997434a50bb8…

MALICIOUS

PDF

70.2 KB Created: 2021-09-03 22:32:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: e114fde3e7832b6266330e9622ef55ca SHA-1: 55e4fe81641b30f55e0ac1494a8064fe2fa2dc0e SHA-256: a2c0997434a50bb866e4b8d6c9f8d8b953c852ff6e9f493b29d2df337f36c767
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged as malicious by a machine learning classifier and ClamAV. It contains a link farm with multiple URLs pointing to potentially compromised websites, suggesting an attempt to redirect users to malicious content or phishing pages. The presence of external URIs and link farm heuristics indicates a pattern of distributing malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://kovtec.pl/eurostyl/photos/file/gatiwis.pdf In PDF document text
    • https://broadstripe.com/wp-content/plugins/super-forms/uploads/php/files/ee0c16b572b0eabf43aaddeb9f3f93ec/vabagasedotos.pdfIn PDF document text
    • http://www.thelawchamber.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c857546e282---linananimixa.pdfIn PDF document text
    • https://www.wizzfizz.com.au/application/third_party/ckfinder/userfiles/files/bevumuwinukowawar.pdfIn PDF document text
    • https://pensiuneavalentina.ro/app/webroot/file/85947010108.pdfIn PDF document text
    • https://educhina.mn/editor/files/69608163833.pdfIn PDF document text
    • http://bbfederico2.net/userfiles/file/57144422094.pdfIn PDF document text
    • http://viaterrestre.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160f40cc876207---10874121101.pdfIn PDF document text
    • http://perlawarmii.pl/userfiles/file/22821278759.pdfIn PDF document text
    • http://toonesk.com/upload/86316629482.pdfIn PDF document text
    • http://cayxaotamphan.net/userfiles/image/file/nuzeburamijodipo.pdfIn PDF document text
    • http://semihkerpiccilervesupersound.com/upload/file/87963720278.pdfIn PDF document text
    • https://www.rowtheerne.com/wp-content/plugins/super-forms/uploads/php/files/f0500673bf7506ae78f7d416a3520f36/58355207045.pdfIn PDF document text
    • http://newtarrytowndeli.com/uploads/files/99105254987.pdfIn PDF document text
    • https://www.ideaklinikkadikoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/16107f8603d9a6---38997762283.pdfIn PDF document text
    • http://angelofthewinds.net/ckfinder/userfiles/files/vamavujibamuvajatikaduti.pdfIn PDF document text
    • http://cargo3030.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160850c6812aa2---netilaposi.pdfIn PDF document text
    • http://wernitznigg.at/files/78891100741.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=lucene+index+pdf+filesPDF link annotation
    • 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_off0000b282.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB282 10292 bytes
SHA-256: 4417e0e0b4c69298abfd16f3578e6a0e172350f1965e56c9ecc9acfc667018ab
font_01_sfnt_off0000c9c3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC9C3 16200 bytes
SHA-256: 0869995f854a3a61968e58f049d36dbe351d3a73f3ce12acccacf1f39e0f61f4
font_02_sfnt_off0000f411.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF411 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1