Malicious PDF — malware analysis report

Static analysis result for SHA-256 889944f682b22d5e…

MALICIOUS

PDF

85.8 KB Created: 2021-08-13 23:33:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 647f06e6294b05d49531c4ffa3c7c0fc SHA-1: 76e5020b107b6d9565be4d40cac2742d5de63a40 SHA-256: 889944f682b22d5efeec2344c9c0e2bd08ffb4b439fc435a0320cf3690577104
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by multiple heuristics as containing a link farm pointing to compromised CMS upload storage. The ML classifier and ClamAV also identified it as malicious, specifically as a phishing trojan. The document body is heavily obfuscated, but the presence of numerous URLs, many hosted on compromised WordPress sites, indicates a phishing or redirection attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://nnk.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16087cc9f8fdfd---3668555201.pdf In PDF document text
    • https://vandolderskb.com/images/usr/5676747563.pdfIn PDF document text
    • https://mavismanagement.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c40c00502aa---ridogego.pdfIn PDF document text
    • https://securitegenerale.tn/userfiles/file/ramunebebinixetex.pdfIn PDF document text
    • http://www.supercarrentalsofmiami.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bec29f9b19b---69177207621.pdfIn PDF document text
    • https://puertoestereo.com/wp-content/plugins/super-forms/uploads/php/files/abjbbh7h469gke0r3rsu69nk35/sawixuzuwowepanedo.pdfIn PDF document text
    • http://bfr-bialapodlaska.pl/userfiles/file/kakajoza.pdfIn PDF document text
    • http://szentimresiklos.hu/upload/file/jisamafetavojenerew.pdfIn PDF document text
    • https://hcs1000.org/wp-content/plugins/super-forms/uploads/php/files/2f606e5b63460a3f44d5a0e66e91d135/57015675002.pdfIn PDF document text
    • http://wjcopy.com/upload/files/97188166487.pdfIn PDF document text
    • http://thegreenlegacykeepers.com/clients/e/e8/e8dc17949b7ef813e9937e453902477f/File/tizukakokalasajupimizuzud.pdfIn PDF document text
    • https://www.etbsupplies.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a1c04b0df93---7540446699.pdfIn PDF document text
    • http://applexin.com/ttpsea/files/file/suwini.pdfIn PDF document text
    • https://lightspec.ca/wp-content/plugins/super-forms/uploads/php/files/731a7f3a39334c77869aceb8708319f2/zexuses.pdfIn PDF document text
    • http://akcjonariusz.com/UserFiles/file/93138308210.pdfIn PDF document text
    • https://www.alphaveneers.com/wp-content/plugins/super-forms/uploads/php/files/354503b6d492d6a7b09dde6791928737/winekezugonipuke.pdfIn PDF document text
    • http://lushexperiences.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607cdcca6ae40---51095981182.pdfIn PDF document text
    • http://cricalliance.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d44635f57a---58712105070.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=12+week+resistance+band+training+programPDF 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_off0000e840.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE840 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010052.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10052 17388 bytes
SHA-256: a6dc485c26b67af9b2c42bbd0ff80525b33a1af5e331359fa6cd284541dec828
font_02_sfnt_off00012e39.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E39 11204 bytes
SHA-256: 6418c6d26a646e27b03806892cc668dfc6c4a944830a2fb30ca1541493027c77