Malicious PDF — malware analysis report

Static analysis result for SHA-256 acc98b535d686476…

MALICIOUS

PDF

82.8 KB Created: 2021-09-08 17:30:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 448761679f2fccff856ed04611b0b2cc SHA-1: d1b3899e7bd362e4f7f2083a2d8b0a81067d13f9 SHA-256: acc98b535d6864766828b8467610dab3cca151bcd0cd9f54017abb00cd8c8475
156 Risk Score

Malware Insights

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

This PDF file was flagged by ML classifiers and ClamAV as malicious. It contains a link farm with numerous URLs, many hosted on compromised WordPress sites or disposable domains, designed to redirect users to potentially malicious content. The primary attack pattern involves tricking users into clicking these links, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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 https://krisoc.ru/uplcv?utm_term=periyar+university+msc+physics+syllabus+2018+pdf PDF link annotation
    • https://www.tyrtaios.gr/ckfinder/userfiles/files/96906188283.pdfIn PDF document text
    • https://www.olympusnorge.no/wp-content/plugins/super-forms/uploads/php/files/lr1acvqs517isvtlattmc2abcu/86322755910.pdfIn PDF document text
    • https://www.havanasalsa-dance-tours.com/wp-content/plugins/super-forms/uploads/php/files/41b3221f17745f071678297941e95986/65676752857.pdfIn PDF document text
    • http://scvumaichiramen.com/uploads/files/biwipurelalefex.pdfIn PDF document text
    • http://pileki.com/imgup/file/16111991005.pdfIn PDF document text
    • http://highendschmiede.de/highendfiles/file/7580291783.pdfIn PDF document text
    • http://webcertain.asia/contentupload/fckeditorUploads/organization_/file/funilevu.pdfIn PDF document text
    • http://iucecb.com/files/file/24718714347.pdfIn PDF document text
    • http://metrominicabs.com/survey/userfiles/files/mesujofexevud.pdfIn PDF document text
    • http://schokoladenfontaene.de/idata/23763292967.pdfIn PDF document text
    • http://mycoapaisyl.com/webimages/files/73346606469.pdfIn PDF document text
    • https://sakesushimn.com/userfiles/files/wofovabujob.pdfIn PDF document text
    • http://www.davidwoodpersonnel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130fcf6537cc---kefaziwaf.pdfIn PDF document text
    • https://infrastone.com/userfiles/files/xevakasiruvekegukugiv.pdfIn PDF document text
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/161345d0cbf433---ferijatatatupe.pdfIn PDF document text
    • http://gabinetpro.gabinetpro.pl/kosmetyczka/krakow/files/korugow.pdfIn PDF document text
    • http://behtarinekhodetbash.com/files/files/63298087709.pdfIn PDF document text
    • http://sqc.jp/user_data/editor/ckfinder/core/connector/php/upload/files/35895731219.pdfIn PDF document text
    • https://ncvpte.in/userfiles/file/buzijojep.pdfIn PDF document text
    • http://irk-yoga.ru/upload/files/dijezonozelupajiga.pdfIn PDF document text
    • https://at2-turbo-j3t.com/contents/files/2507971347.pdfIn PDF document text
    • https://odontologosmalca.com/images/userfiles/file/biwigijebemipu.pdfIn PDF document text
    • 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_off0000d6d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6D5 18960 bytes
SHA-256: b56cc83b8d9448d5fd338dfec235d5cfedbf94a4445d3df21b6e3782ea8ff653
font_01_sfnt_off00010808.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10808 11688 bytes
SHA-256: 0484cfb9e6ac0f9e1b3c902e6802695303a8befa519b647848fdbe47da695479
font_02_sfnt_off00012392.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12392 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1