Malicious PDF — malware analysis report

Static analysis result for SHA-256 81a59ab8fc1b396a…

MALICIOUS

PDF

83.5 KB Created: 2021-06-27 11:42:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: dce732ac4db2202482b9103084cf4c97 SHA-1: b3110cf3d5ae22467a8e4c57f825409e52b3f668 SHA-256: 81a59ab8fc1b396ac2870fcea491b5d4f09bc671f5e7616611c17c74df6c1e85
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links, many hosted on compromised WordPress sites, suggesting a link farm designed to redirect users. The document body is heavily obfuscated and unreadable, providing no direct clues to its purpose beyond the presence of these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://baharemadinah.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f1ccd1e7e6---xerakapajuwexapeluxidexu.pdf In PDF document text
    • http://studionegro.net/userfiles/files/33876995421.pdfIn PDF document text
    • http://angelcabrera.com/FCKfiles/file/5238217782.pdfIn PDF document text
    • http://herodumpsterrental.com/wp-content/plugins/super-forms/uploads/php/files/0fc363b5b554e88438ad70df0a4f9b20/98088561264.pdfIn PDF document text
    • https://3dreamstudios.com/wp-content/plugins/super-forms/uploads/php/files/46b78ba840cb756b44238e452a5c3095/muridonozexevof.pdfIn PDF document text
    • https://glosunspa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160834553218f7---72557879262.pdfIn PDF document text
    • https://imapcb.org/wp-content/plugins/super-forms/uploads/php/files/v0il9td05a5ueva8bmjlspi7o3/junumepususase.pdfIn PDF document text
    • http://www.belladermeestetica.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607960537f141---witaw.pdfIn PDF document text
    • https://advance-pack.com/editor_upload/file/rokasulitonopadavekusisef.pdfIn PDF document text
    • https://djhelaly.com/wp-content/plugins/super-forms/uploads/php/files/5516e4561ba1f5a4b318477784835704/fivopaz.pdfIn PDF document text
    • https://intelean.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a5e9189c920---fadamatow.pdfIn PDF document text
    • http://iglozawiercie.pl/zdjecia/file/64816790625.pdfIn PDF document text
    • http://www.lbf-cosmetics.com/website/wp-content/plugins/formcraft/file-upload/server/content/files/160af6f877250b---mujaduvoxun.pdfIn PDF document text
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a407968b175---dodapopokowepepovilejew.pdfIn PDF document text
    • http://eortak.com/img/fck_temp/file/favagetut.pdfIn PDF document text
    • https://archcosmeticstudio.com.au/wp-content/plugins/super-forms/uploads/php/files/04760b4b431a0971aa6a9df4ff0a6bd3/7120798472.pdfIn PDF document text
    • https://agsposure.org/wp-content/plugins/super-forms/uploads/php/files/dc75f61c66198d8f80e61a05c668175a/kazolowifejenuwipofojetir.pdfIn PDF document text
    • http://mid-europe-ex.com/images/blog//file/jepomo.pdfIn PDF document text
    • http://evabody.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1607f8a0945108---23290729724.pdfIn PDF document text
    • https://gresathouse.com/wp-content/plugins/super-forms/uploads/php/files/2d93ddf3fd7bd31038d8d7a35a2bec8e/kemugaduse.pdfIn PDF document text
    • https://pmeds.us/userfiles/file/ratibiwelafapobod.pdfIn PDF document text
    • http://rolmech-strzelno.pl/Upload/file/zafupupiranedudufone.pdfIn PDF document text
    • http://sbs-group.co/userfiles/files/mefoner.pdfIn PDF document text
    • https://luxartparquet.com/wp-content/plugins/super-forms/uploads/php/files/1a744e0073978299f64d91ef9b7c077a/305046183.pdfIn PDF document text
    • https://www.hontoys.com.au/wp-content/plugins/super-forms/uploads/php/files/khv1sl26hj56vk5m3p9psu6trm/2622865991.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=distended+meaning+in+marathiPDF 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_off0000e183.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE183 18544 bytes
SHA-256: 3276b4f207efb1ab74c52cc2c4462d49d4483def44cb2329952f59e78bd809bc
font_01_sfnt_off000110e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110E7 10532 bytes
SHA-256: 181a5bcdfd7dfd235f7eda4fe2dc97b9751df2dd5a07449b2b9a20a978a93509
font_02_sfnt_off00012879.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12879 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1