Malicious PDF — malware analysis report

Static analysis result for SHA-256 91d1c1513ee7b15f…

MALICIOUS

PDF

77.3 KB Created: 2021-09-25 03:56:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: e2f9fbc8214a7ec1bf11fdec05e0c232 SHA-1: be08f32e202789b454d14c105c6f9791e874281d SHA-256: 91d1c1513ee7b15fd806a3e283285d376de540b207d2d4fae3d2c89ebcaba520
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected by ClamAV as Pdf.Phishing.Trojan and an ML classifier flagged it with high confidence. The PDF contains numerous embedded URLs, many pointing to domains that appear to be part of a link farm, suggesting a phishing or redirection attempt. The heuristic PDF_SEO_DISPOSABLE_LINK_FARM indicates a deliberate attempt to create a large number of links on disposable hosting, reinforcing the malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://clubslotalmatriche.com/calcas/file/66715828250.pdf In PDF document text
    • https://clubsecurite.fr/webroot/upload/files/xelaroviwapikif.pdfIn PDF document text
    • https://brs.jo/userfiles/files/jowatofowigedef.pdfIn PDF document text
    • http://autobedrijvenindex.nl/images/uploads/94292294943.pdfIn PDF document text
    • http://albertf.madteam.net/ckfinder/userfiles/files/lojekufoteragez.pdfIn PDF document text
    • https://www.orthovision-lublin.pl/ckfinder/userfiles/files/bitiwubavi.pdfIn PDF document text
    • http://yotlist.com/uniformkontakt/userfiles/image/files/33683457977.pdfIn PDF document text
    • https://autohausnschmidt.de/userfiles/file/zutevugejilarowibix.pdfIn PDF document text
    • http://www.cemeba.com/uploads/ckfinder/files/salemofezati.pdfIn PDF document text
    • https://www.domaine-boussard-chablis.fr/ckfinder/userfiles/files/77475969779.pdfIn PDF document text
    • http://gesundheit-im-blog.de/userfiles/file/rifubugezibevudowewo.pdfIn PDF document text
    • http://huyminhplastic.com/upload/files/91814001622.pdfIn PDF document text
    • http://stavo-bazar.cz/userfiles/file/9748399046.pdfIn PDF document text
    • http://indigobaby.eu/upload/files/42323351484.pdfIn PDF document text
    • http://kiapelhrimov.cz/UserFiles/File/42794148361.pdfIn PDF document text
    • http://mopi.eu/ckfinder/userfiles/files/71019415492.pdfIn PDF document text
    • http://turbotechnik24.de/userfiles/file/lufirurilogematel.pdfIn PDF document text
    • https://collinite.pl/userfiles/file/lopinosivatuwojo.pdfIn PDF document text
    • http://stefanourso.com/public/userfiles/file/ruvono.pdfIn PDF document text
    • https://sukaunited4d.vip/contents/files/vogajixufobepibofozozepib.pdfIn PDF document text
    • http://saatgaamkansarasamaj.com/admin/uploads/files/15249555611.pdfIn PDF document text
    • http://mrspk.com/ckfinder/userfiles/files/sunejotipuzerupomiwitafe.pdfIn PDF document text
    • https://ms01bet.net/contents/files/85326497373.pdfIn PDF document text
    • http://parentini.it/userfiles/files/88242048416.pdfIn PDF document text
    • http://makesrealsense.com/ckfinder/userfiles/files/34697889081.pdfIn PDF document text
    • http://la-roofers.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613548bb3475b---tutujaginibebatos.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=davao+del+sur+postal+codePDF 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_off0000c256.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC256 10476 bytes
SHA-256: 978a562ed87a8311607b9d095530ba10c2ae5cfaaa8e5d521437799c4a1a1b9d
font_01_sfnt_off0000da5c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA5C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f26e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF26E 20580 bytes
SHA-256: c10a1ed1d950049d9b31a3160c2ddfb5e02c50845398466289f6d991f0269944