Malicious PDF — malware analysis report

Static analysis result for SHA-256 c5d1f1e329226de4…

MALICIOUS

PDF

73.9 KB Created: 2021-09-06 23:08:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a6b761d834806bd52876715666d79254 SHA-1: c8dcd3e272aff9230ea8bb313da52d8935c001e3 SHA-256: c5d1f1e329226de434cf7599f94a497429f711f6bd445fa3611f019d6617868b
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample contains embedded JavaScript and is flagged by ML classifiers and ClamAV as malicious, specifically a phishing trojan. It functions as a link farm, directing users to other PDF files hosted on compromised WordPress sites and disposable domains, likely to facilitate phishing attacks or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://wadsoda.com/UserFiles/File/purixiwezirakuzerolu.pdf
    • http://jr.ac.th/ckfinder/userfiles/files/61689280079.pdf
    • http://kocavietnam.com/upload/files/5398280595.pdf
    • https://detectiveoffice.net/userfiles/file/sewegotujavuruwejabed.pdf
    • https://www.mclarenpress.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b759a77f9ef---revuzuponekirewiz.pdf
    • https://lisacutler.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bbaf98c78dc---35219743681.pdf
    • https://nscs.org/wp-content/plugins/super-forms/uploads/php/files/4a10d6944e9d1f50ffaa7f3c7cb22b28/29301628774.pdf
    • https://certifiedmoversinc.com/wp-content/plugins/super-forms/uploads/php/files/857d9cd6b496a8cb8314dd202c870bff/64715725775.pdf
    • https://www.sevgiliyevideo.net/wp-content/plugins/formcraft/file-upload/server/content/files/160c23dd060e07---kusofuxedonuwexovininiku.pdf
    • http://machi-tomo.xyz/js/ckfinder/userfiles/files/kojufum.pdf
    • https://eduinfinite.com/wp-content/plugins/super-forms/uploads/php/files/c825c9ac4811e3bbf98b27d3a68580a6/75245918895.pdf
    • http://www.tobywells.org/media/fckdir/file/kikilojawu.pdf
    • http://naasschoolofmotoring.ie/fckeditor/userfiles/file/guluvunupewodusi.pdf
    • https://fleuriste79.fr/ckfinder/userfiles/files/mivipalesevuritodupoda.pdf
    • https://lorenzonimmigrationlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076a3fd38b1e---89283733277.pdf
    • https://www.hed-endo.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1608b05bc61523---nifijunajewi.pdf
    • http://jointrilogy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f604e03e80---jebajawexaweg.pdf
    • http://fine-cottage.ru/userfiles/files/xegajideterogajafepa.pdf
    • https://legacydockandmarine.com/wp-content/plugins/super-forms/uploads/php/files/43d9a5c9a9238afb748ba7f41667f39b/95927857772.pdf
    • http://www.insight-assessment.com/ckfinder/userfiles/files/barejutuki.pdf
    • http://nachhilfeschule.havonix.com/ckfinder/userfiles/files/bafas.pdf
    • http://consulcongress.it/uploads/assets/file/tuvoxonedidigu.pdf
    • http://birons.net/wp-content/plugins/super-forms/uploads/php/files/46173ae5bd4e7238effd3c3e60684184/52351711317.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=kanji+n5+list+pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000bcd0.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xBCD0 16792 bytes
font_01_sfnt_off0000d4e7.bin
fb4210d54caaf38e97b65488c32507537ab3ce627e23211b6c553f646e613c39
pdf-font-stream PDF embedded font (sfnt) at offset 0xD4E7 10396 bytes
font_02_sfnt_off0000ec7e.bin
1d187f2c5a6cdcc70bd7253f354a16f0f42c1db12d3ff179b7065c0905ccfdd7
pdf-font-stream PDF embedded font (sfnt) at offset 0xEC7E 17552 bytes