Malicious PDF — malware analysis report

Static analysis result for SHA-256 b21a3f2ba15dae31…

MALICIOUS

PDF

86.3 KB Created: 2021-09-01 05:21:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ce9ff216cca370ff610cb1ea85e7f608 SHA-1: 20aa9207714cfb81d3bd6c19900f6a35f3a1f107 SHA-256: b21a3f2ba15dae31dfc9a609967e4f7f5c018505b499d47ff018727e0fb9b516
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous links, many pointing to compromised WordPress sites, indicating a link farm designed to redirect users to potentially malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery. The file's structure and link distribution align with techniques used to obscure malicious destinations.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://idealist.ro/userfiles/file/47118209522.pdf
    • https://cosalesrep.com/wp-content/plugins/super-forms/uploads/php/files/07ecfe22da888becd882a8c58e1bad9e/4803942001.pdf
    • https://ntpuvoice.com/ckfinder/userfiles/files/9841905530.pdf
    • https://futuresbuilder.net/dayafter/uploadimages/newsimages/file/menotowe.pdf
    • http://kammatrans.com/userfiles/files/kubodozupedajakifuj.pdf
    • http://primaneighbors.com/userimages/tojenu.pdf
    • https://gaseg.com/wp-content/plugins/super-forms/uploads/php/files/n6rfgbu7b5182qvk80frclen9u/jigejagazuxokizo.pdf
    • https://www.siemers-deutschmann.de/wp-content/plugins/super-forms/uploads/php/files/8rt99dh6tc6p0phbvohcgdnn4m/gepobuzegawekebilatijaxij.pdf
    • https://zabulgaria.org/userfiles/file/kewul.pdf
    • http://firstcuwire.com/file_media/file_image/file/35821418703.pdf
    • http://run2endalz.org/clients/2/2b/2b4973775a35d8819257a28a16fdea67/File/26066406423.pdf
    • http://xn--80aaaaaikdebj9ccf1ayja1b5a3q.xn--p1ai/ckfinder/userfiles/files/45254856717.pdf
    • http://psychologadamczak.pl/userfiles/file/35333615206.pdf
    • http://www.theflightfest.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c7a35d2b608---nedakawopurulovatarisut.pdf
    • http://vilaportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa3da593b3a---3966373506.pdf
    • https://razdolle.by/wp-content/plugins/super-forms/uploads/php/files/obb3rfqffltma8ol1su1lnnc03/18553437517.pdf
    • http://vom-ragnaroek.de/uploads/file/xeluja.pdf
    • http://www.startservis.sk/novy/ckfinder/userfiles/files/81477368552.pdf
    • https://atvatextile.com/upload/ckfinder/files/78187047599.pdf
    • https://nikosdimos.gr/userfiles/file/gopumamimap.pdf
    • https://fcr-fomentoconsumoerenda.com/uploads/files/pikuxuwiwirupurixo.pdf
    • https://www.parkgest.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160bb9e37e602b---76807912178.pdf
    • http://originalbau.hu/imagesfiles/donibemagufuzinapar.pdf
    • http://aaaexpressheating.com/userfiles/file/zasoluxigarenaxelarex.pdf
    • http://shinex-auto.com/userfiles/file/momazilamumisajev.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=understanding+power+purchase+agreements
    • 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_off0000eaba.bin
479749c2cba3df39bd174f509d96ad0f4b153124366b0e78c31a05cd35fd43d4
pdf-font-stream PDF embedded font (sfnt) at offset 0xEABA 17932 bytes
font_01_sfnt_off000118e6.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x118E6 16792 bytes
font_02_sfnt_off000130fd.bin
edb7ec6b2f33fbca5237f482dbdf153e0daf92450372d2f1781274240f107a67
pdf-font-stream PDF embedded font (sfnt) at offset 0x130FD 11108 bytes