Malicious PDF — malware analysis report

Static analysis result for SHA-256 538a145021fe2262…

MALICIOUS

PDF

79.0 KB Created: 2021-09-05 07:12:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d42c2db1af4674b4704cc7d963278c88 SHA-1: c1665cca3506aa1483476e51f19bd4bfcf49e864 SHA-256: 538a145021fe2262f15878c26f6f35caa82dc359854046d9842f960f7b090e88
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. No scripts were extracted, and the document body was unreadable, but the heuristic findings are sufficient to assess the attack pattern.

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 https://apotekatia.ba/fajlovi/91089660080.pdf
    • http://pvsystexperts.com/wp-content/plugins/super-forms/uploads/php/files/3vmcj9a31re8nh87visbke7o21/gabijutobebirevemafo.pdf
    • https://aradovan.com/userfiles/file/jofakozudalumebu.pdf
    • http://mko-yug.ru/wp-content/plugins/super-forms/uploads/php/files/0a72379de95dbb147fb2d08c26a6f8f8/5204434912.pdf
    • http://www.smartlandgroup.com//ckfinder/userfiles/files/fumobefikexesunizo.pdf
    • http://getawaynewzealand.co.nz/wp-content/plugins/formcraft/file-upload/server/content/files/1610d75f2a4a3e---45464901726.pdf
    • https://anakmeong.com/contents//files/fuzuvubekopusixek.pdf
    • https://atolab.it/wp-content/plugins/super-forms/uploads/php/files/438c40b4fb0232315476e4c53f013c99/zirurezezuwevewupideloxef.pdf
    • https://doctorchina168.com/upload/files/16830445050.pdf
    • http://ikhmongol.mn/ckfinder/userfiles/files/putasowepidifolugokagek.pdf
    • http://bagiez.com/userfiles/file/susafarowaselajosagilit.pdf
    • https://www.properties-thassos.com/wp-content/plugins/super-forms/uploads/php/files/4nogq11nfqkk07vg4ql90d8eir/gujedopupogidonedazo.pdf
    • http://ourjamesfamilyhistory.com/clients/1/14/146a9f92d0a296c7c29e793db058bb30/File/86985374249.pdf
    • http://www.vivelamusica.es/wp-content/plugins/formcraft/file-upload/server/content/files/160e5a7b298293---20797640014.pdf
    • https://valleyrestoration.net/home/apf/public_html/ckfinder/userfiles/files/guleditopanigusexabup.pdf
    • http://futuralagoparking.eu/userfiles/files/nenefumuwudo.pdf
    • http://www.aportecnica.com/imagenes/editor/file/73918023579.pdf
    • http://samurairamenbar.com/uploads/files/89250543069.pdf
    • https://regalcabs.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160e7db177b03f---tikewovuvenalosekamodez.pdf
    • http://heorungminhphat.com/luutru/files/zodozotow.pdf
    • https://33mobility.net/uploads/files/9382583911.pdf
    • http://signexpowholesale.com/project-new/christianbook/upload_images/file/73826581507.pdf
    • http://fruhmann-elektrotechnik.at/tolelavize.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=subramanya+bhujangam+telugu+pdf+download
    • 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_off0000c697.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC697 16792 bytes
font_01_sfnt_off0000deae.bin
fa36710f707ef934f0df6d2a9a18e5104a20eae5f84bc7f0117f36dc8ab0a46a
pdf-font-stream PDF embedded font (sfnt) at offset 0xDEAE 11328 bytes
font_02_sfnt_off0000f8d8.bin
206124108f782d653e3b928319f92b809cbf9c1a63ae2c786e6a587d182fffe6
pdf-font-stream PDF embedded font (sfnt) at offset 0xF8D8 20232 bytes