Malicious PDF — malware analysis report

Static analysis result for SHA-256 1da86973eed5f534…

MALICIOUS

PDF

78.8 KB Created: 2021-09-02 08:13:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 933e4f88f72e92452ee61cb784671346 SHA-1: 5dd34eb4996294acd4f1d04da95ff533bd028fce SHA-256: 1da86973eed5f534c15c8f338cc79e1f4d9394a969049e3a9a9e55a492cb9443
156 Risk Score

Malware Insights

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

The PDF file contains a link farm with numerous URLs pointing to compromised WordPress upload directories and disposable hosting domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to lure users to phishing or malware distribution sites. No scripts were extracted, and the document body was unreadable, so the primary attack vector appears to be the embedded links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

Heuristics 6

  • 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.
  • 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://dermalab.pl/userfiles/file/fiwoniluvesijevak.pdf In PDF document text
    • https://www.apartamentselsllacs.com/wp-content/plugins/super-forms/uploads/php/files/alp8nfj8f7eef8q6b07n4g98bj/46977733568.pdfIn PDF document text
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160727c86897e8---70098871448.pdfIn PDF document text
    • http://arisutour.com/ckupload/files/47302247000.pdfIn PDF document text
    • http://evabody.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160bbbec82dea1---67878860858.pdfIn PDF document text
    • http://newfieldclassof1982.com/clients/6/69/69e49ffade321d977af769e13f9f004b/File/lagusukufonilogem.pdfIn PDF document text
    • http://avtoarka.ru/wp-content/plugins/super-forms/uploads/php/files/3deaae844eb113c258d915704565b355/misedul.pdfIn PDF document text
    • https://altonika.pro/files/fck/file/3716096223.pdfIn PDF document text
    • http://dobryremont.pl/ebobas/portal/app/webroot/img/tmp/file/16206247853579.pdfIn PDF document text
    • http://rlangkhan.com/upload/userfiles/files/losevelaluf.pdfIn PDF document text
    • http://barcelonasixtytwo.com/userfiles/file/demitefulav.pdfIn PDF document text
    • https://alphacleanwashing.com/wp-content/plugins/super-forms/uploads/php/files/37acc07b7b1c604fad3497f9caa72e5d/82260216955.pdfIn PDF document text
    • https://altaitur.com/ckfinder/userfiles/files/24646416471.pdfIn PDF document text
    • http://iamsoldierfit.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607497691f876---zovefijoburadusuk.pdfIn PDF document text
    • http://fabrykakonwersji.pl/wp-content/plugins/super-forms/uploads/php/files/2ec12381b8e80df736dd89e2dbdb78ae/raligotozelejux.pdfIn PDF document text
    • http://thrifty-uy.com/files/others/zopenodudiz.pdfIn PDF document text
    • http://mas.vacations/wp-content/plugins/formcraft/file-upload/server/content/files/16093f964d7f22---wajuzifowofodeza.pdfIn PDF document text
    • http://ahcxdq.com/uploads/file/222357296055.pdfIn PDF document text
    • http://szermgrt.hu/uploads/ckfinder/userfiles/files/35717635412.pdfIn PDF document text
    • https://www.uniqueartzz.com/wp-content/plugins/super-forms/uploads/php/files/7h9n67ekulk21comlfs3898vpe/22492927573.pdfIn PDF document text
    • https://polskieplytki.com/wp-content/plugins/super-forms/uploads/php/files/f4cf80d579285efdab9091c286dad104/48784376678.pdfIn PDF document text
    • https://www.oneirishrover.com/wp-content/plugins/super-forms/uploads/php/files/71c1f84dbc67f5259536e8a7b65e304e/68390050692.pdfIn PDF document text
    • http://stepsforstarlight.org/clients/c/c6/c668404594a1c08d975ab50c7bec58f6/File/goritakepi.pdfIn PDF document text
    • https://www.hospedeagora.com.br/wp-content/plugins/super-forms/uploads/php/files/t5dl994tguntlgfmltegg1d33u/zufuxepupov.pdfIn PDF document text
    • https://acrgroup.nl/userfiles/file/duwejaxuridejowisevefugi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=correlation+between+two+sets+of+dataPDF 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_off0000d149.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD149 10604 bytes
SHA-256: 8ced0b97942e250423bbe43bb795462eb4c45d66dd4ce587972f833208a75a43
font_01_sfnt_off0000e9b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9B6 16576 bytes
SHA-256: 26310dadf81d5b90e138616421d0dd3713b2d17e884deeeb19c34947c51a6d5a
font_02_sfnt_off0001142b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1142B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1