Malicious PDF — malware analysis report

Static analysis result for SHA-256 4156756edb6d07f3…

MALICIOUS

PDF

85.5 KB Created: 2021-07-03 00:57:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2e9d25bd02d59af21a944dc2ade5b04d SHA-1: f1ceb83cdb098ef641e910034e05c1ad250da521 SHA-256: 4156756edb6d07f364caf4bab315531c8da7e7bb3a84e89a177738ed48039162
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The document functions as a link farm, containing numerous URLs pointing to compromised WordPress sites and disposable domains. These links likely serve as lures for phishing attacks or to distribute further malware payloads. No scripts were extracted, but the structure suggests it's designed to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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 https://synerhu.ru/uplcv?utm_term=meaning+for+assume
    • https://voolabs.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e772b21061---42955239709.pdf
    • https://accuratesearch.com/userfiles/file/52007604884.pdf
    • http://elijasprojekts.lv/files/file/64138556331.pdf
    • http://fotografiafrancescosomma.com/userfiles/files/4638679526.pdf
    • https://asiaviews.org/wp-content/plugins/super-forms/uploads/php/files/evo4ppvqlmi8e94oaloeu0a7g1/kupakebabobu.pdf
    • http://yokohama-model.com/userfiles/files/4165285432.pdf
    • https://www.saenger-ohg.de/wp-content/plugins/formcraft/file-upload/server/content/files/16085377e4a851---59781178451.pdf
    • https://guruamardaspublicschool.com/userfiles/files/ginofuk.pdf
    • http://ipjanah.ir/wp-content/plugins/super-forms/uploads/php/files/fdnj7njl9ftjemms5lo548u2o5/sirariwizokikatobugif.pdf
    • https://admonks.ru/wp-content/plugins/super-forms/uploads/php/files/fdca23ed0e3a0f544d15c0c71c9a7101/98554108363.pdf
    • http://ankamet.com/userfiles/file/86226531275.pdf
    • http://protech.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/160924b0e2509e---wuvaluv.pdf
    • http://propellerclubsandiego.org/uploads/files/kovojikogadotisipux.pdf
    • https://mytalk7.com/_UploadFile/Images/file/62472397608.pdf
    • https://www.landalastadservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e4ceabb07a---70926647952.pdf
    • http://iseveranscopy.com/upload/editor/file/36305652871.pdf
    • http://www.mtpartnersfl.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090f6ccd8264---nidenogurajeko.pdf
    • https://prana.video/wp-content/plugins/super-forms/uploads/php/files/63atf806nmna17huda69533a56/24705592571.pdf
    • https://www.lesson-online.org/wp-content/plugins/super-forms/uploads/php/files/h0jnggjgkllvrbsadbr5cml7i6/43614040585.pdf
    • http://creativeindustries.ru/uploads/userfiles/file/31647264370.pdf
    • https://www.lowdoc-loans.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1608cf130c82ff---34958300252.pdf
    • https://www.hadlowsecurityshutters.com/wp-content/plugins/super-forms/uploads/php/files/1e485b1456cfe97805229be3a74f17f1/86615956032.pdf
    • http://neilreardon.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/jotekijopapikevud.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_off0000e897.bin
74996c219eaa22729ee86d04b4bcc3274184b0c524d898e828a464febd0c3625
pdf-font-stream PDF embedded font (sfnt) at offset 0xE897 18516 bytes
font_01_sfnt_off0001190d.bin
e6481d54665280cbbbdf18c4951e21c82b200a8847153eeb5cc98f5e5333c579
pdf-font-stream PDF embedded font (sfnt) at offset 0x1190D 10508 bytes
font_02_sfnt_off000130ed.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x130ED 16792 bytes