Malicious PDF — malware analysis report

Static analysis result for SHA-256 3f4a0657a3d56904…

MALICIOUS

PDF

82.6 KB Created: 2021-10-06 13:48:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: 0674de6ef73fdffce5684935fc0ad9e7 SHA-1: da19d5189ce6b0fe9ea8cbdb4cd203b6839ab16d SHA-256: 3f4a0657a3d56904308466fed5f30ca1ec2eb04d48adb9458235669840ba431d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ML classifiers and ClamAV as malicious. It contains numerous embedded URLs, many of which point to compromised CMS upload directories or disposable hosting, indicating a link farm designed to redirect users. The presence of these links suggests an attempt to direct users to malicious sites for phishing or further payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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 http://minhanh.com/files/goxifolaxifinutirofaben.pdf In PDF document text
    • http://iwilldoit.ru/uploads/files/files/3748096086.pdfIn PDF document text
    • http://kingspec.su/wp-content/plugins/super-forms/uploads/php/files/p2a4vkherp75oop1rvi4ebfpar/15295441630.pdfIn PDF document text
    • http://studiotecnicolamanna.com/userfiles/files/wogizitijijido.pdfIn PDF document text
    • https://infrapanel-alegjobbfutes.hu/userfiles/file/56932377461.pdfIn PDF document text
    • http://status-go.net/gfx/userfiles/files/49631883337.pdfIn PDF document text
    • http://96stone.ru/userfiles/file/10306415577.pdfIn PDF document text
    • https://nikosdimos.gr/userfiles/file/65148193945.pdfIn PDF document text
    • http://nguyenthaotech.com/upload/files/11262156110.pdfIn PDF document text
    • http://cnc-soustruzeni.cz/files/file/patapiwikelavufagogewenof.pdfIn PDF document text
    • http://kommunikator.nu/demo/userfiles/file///61158932998.pdfIn PDF document text
    • http://dighakanchaninternational.com/FCKeditor/file/96728773245.pdfIn PDF document text
    • https://absoluteanytime.com/media_file/files/files/xuxewabaxakadekefine.pdfIn PDF document text
    • http://tdvvietnam.vn/webroot/img/files/62579683178.pdfIn PDF document text
    • http://omgmediatank.com/userfiles/files/vamezon.pdfIn PDF document text
    • https://stormester.no/files/file/zobanegovaliwuxasopumem.pdfIn PDF document text
    • http://ksiclubbiz.ksiclub.org/svnprojects/DHD/Source/images/files/355991154.pdfIn PDF document text
    • http://cicm2015.mist.ac.bd/app/webroot/ckfinder/userfiles/files/tojoradobanorapevavapiw.pdfIn PDF document text
    • https://infypos.com/infyposcms/media/10239314777.pdfIn PDF document text
    • https://sibois.eu/userfiles/file/70093632899.pdfIn PDF document text
    • https://www.beadvised.co.uk/wp-content/plugins/super-forms/uploads/php/files/4e9328b3df62e0350ac5a8a58238dd4a/52454149145.pdfIn PDF document text
    • http://shimamura-mail-order.com/userfiles/file/kutikupawixi.pdfIn PDF document text
    • http://becucci.it/userfiles/files/tuxikakuvax.pdfIn PDF document text
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/9s2cic5lbvs45kl98am07kh7so/zadukimokajize.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=exercise+9.2+class+12PDF 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_off0000dc1a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC1A 18692 bytes
SHA-256: 229103aaba6020ba46e06b6f674a66ae6744b0f6ac1a67123a600b165c9aaa81
font_01_sfnt_off00010d4c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D4C 10392 bytes
SHA-256: fc7ecf0fab871c0f455dc6e2205feeb77c7fce1eade46163fc3f16c824c1a61d
font_02_sfnt_off00012510.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12510 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1