Malicious PDF — malware analysis report

Static analysis result for SHA-256 81d076cb3e9d9ba6…

MALICIOUS

PDF

91.3 KB Created: 2021-07-22 23:28:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: f1865797780b74ec57c8127b46e97d17 SHA-1: 8eed2a5a4726c4777144c4fee6745c2b4d3bdb63 SHA-256: 81d076cb3e9d9ba6589c22f11456697aa3c7910ada07dbc72e6f84fc726eb040
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a phishing or trojan threat. It functions as a link farm, with numerous embedded URLs pointing to compromised WordPress upload directories, likely intended to lure users to malicious content. The document body is unreadable, but the heuristic findings strongly suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://gsoam.ge/wp-content/plugins/formcraft/file-upload/server/content/files/160793b6a92163---zedoxel.pdf In PDF document text
    • https://www.cdscabling.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160944ded91bd9---80521441977.pdfIn PDF document text
    • https://pluckywize.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089321f99fbf---puvoresonegijefogigo.pdfIn PDF document text
    • http://atomleasing.ru/media/File/76161647043.pdfIn PDF document text
    • https://sip7.pl/autoinstalator/sip7.online/wp-content/plugins/super-forms/uploads/php/files/3b49db13981cca00b1fe50866e271eeb/83464164924.pdfIn PDF document text
    • https://ethiquedevelopers.com/wp-content/plugins/super-forms/uploads/php/files/b366aa28043ec71798b4a6f2840557d0/xinitewifaparabuwejelidam.pdfIn PDF document text
    • https://musikkursus.dk/userfiles/file/lagavofipitutifob.pdfIn PDF document text
    • http://cmtsport.com/pliki/40024859936.pdfIn PDF document text
    • http://www.putnamtaxi.net/wp-content/plugins/formcraft/file-upload/server/content/files/160c2af1c27420---bawujavevutememujafexejas.pdfIn PDF document text
    • https://criteriacambio.com.br/wp-content/plugins/super-forms/uploads/php/files/sg7eh8r7ss1khvquadhevoa66c/daduxuxireja.pdfIn PDF document text
    • https://xo-sound.ru/userfiles/file/30006754523.pdfIn PDF document text
    • http://www.tokyomagic.jp/images/library/File/pokutozikut.pdfIn PDF document text
    • http://www.miamiairportlimo.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a8af0f173a3---gudepirazaxej.pdfIn PDF document text
    • http://purofirstli.net/userfiles/file/52927611682.pdfIn PDF document text
    • http://mdsalon.ru/img/lib/file/nelorojugun.pdfIn PDF document text
    • https://asset-books.com/userfiles/file/zexiwe.pdfIn PDF document text
    • http://www.urbanwaterways.info/files/valopajobuk.pdfIn PDF document text
    • http://akcjonariusz.com/UserFiles/file/50176947481.pdfIn PDF document text
    • http://boulderdivorcelaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c9659364523---lizitopivemezufigabe.pdfIn PDF document text
    • https://www.golaw.net/wp-content/plugins/formcraft/file-upload/server/content/files/16088b1e4bd2a8---rosigivemasoz.pdfIn PDF document text
    • https://www.hed-endo.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160cbe1b74616b---85504043517.pdfIn PDF document text
    • https://sportli.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160afa2247d377---diniraza.pdfIn PDF document text
    • http://abaj.cz/UserFiles/File/sumitoseboganarad.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=different+types+of+conflict+in+literaturePDF 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_off00010262.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10262 10688 bytes
SHA-256: bea86b29e9fc71842e825bfdca836d1f0aa0e37f2ae0e9a0062e6a06d4f99e58
font_01_sfnt_off00011b15.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B15 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013327.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13327 16792 bytes
SHA-256: d631058d6196844bcabf0f117e013c5d230d08b0ce0e188179742ccb3362c84a