Malicious PDF — malware analysis report

Static analysis result for SHA-256 98000b94ac5c2c63…

MALICIOUS

PDF

87.8 KB Created: 2021-07-15 17:05:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 3b3949274c1efd442e30003ae778a081 SHA-1: 31487e285156f5b7f9bfb0c3c29db087a898ad85 SHA-256: 98000b94ac5c2c6346b7f55ccb73c2f94db7c04f87cb8b024b0e17182187d35f
156 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as 'Pdf.Phishing.Trojan' and a machine learning classifier indicated a high probability of maliciousness. Static analysis revealed the document functions as a link farm, containing numerous URLs pointing to compromised WordPress sites and disposable hosting. These links are likely intended to redirect users to phishing pages or download further malware.

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://www.anandtirth.com/wp-content/plugins/super-forms/uploads/php/files/3c5j920nhcrv7rp2ubou32c387/rilerofutafuxod.pdf
    • http://tai-yang.tw/taiyang/upload/file/levajuxivovefakexarolage.pdf
    • http://www.urbanwaterways.info/files/vakijekamip.pdf
    • https://shriayurvednagpur.org/public/ckfinder/userfiles/files/58354183363.pdf
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080ccc2910ab---36908576837.pdf
    • https://www.carlosfunes.es/wp-content/plugins/formcraft/file-upload/server/content/files/160af923650f0c---xabimugorovurote.pdf
    • http://decaiyun.com/upload/file/210613035442478434pma4xn3ojd4w.pdf
    • http://uelzecht.lu/userfiles/files/53061819837.pdf
    • http://ithaca1960.com/clients/8/87/874e400c25abfb160fd1c0cf9913fcd0/File/disajerolasavesalabaf.pdf
    • http://njuhome.pl/ckfinder/userfiles/files/radikisilajuga.pdf
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160840f40606ba---bivamufivoja.pdf
    • http://fine-cottage.ru/userfiles/files/30106953547.pdf
    • https://media-get.com/userfiles/files/vimewawunufukinojegenezo.pdf
    • http://www.northern-japan.com/image/upload/File/kagozofukogozodiduf.pdf
    • https://www.accidentinjurylascruces.com/wp-content/plugins/super-forms/uploads/php/files/rmcpo5gqh957itvgc0ctlvl0tp/fatetamitupuxenifit.pdf
    • https://anmoul.com/userfiles/file/wixemeku.pdf
    • https://fablab808.com/nbloom/fckuploads/file/razufitukeninabekixorule.pdf
    • http://baovephuongtroi.com/vietkiendo/upload/file/sinisupurijosumulop.pdf
    • https://zweiund40.com/wp-content/plugins/super-forms/uploads/php/files/78fo53auqhm1p3phvn6b1vvl77/17353708730.pdf
    • http://elonsummerstorage.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608045cfea873---82145879110.pdf
    • https://monographie.com/ckfinder/userfiles/files/rapesez.pdf
    • https://cffcommunications.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/1607f2ca82d43b---fukonadozibogivisebavenu.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=cell+structure+in+prokaryotes+and+eukaryotes
    • 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
stream_004_off00012670.bin
c95d2e9d7a5f8daeeb51208d65edb53b09bcc6bc440df95125d2b31e7b4359ea
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x12670 16792 bytes
font_00_sfnt_off0000f532.bin
077781917cd84fdab35e3873cc0cb7fce29b012d1373f5c8eff0d09617e458d1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF532 10844 bytes
font_01_sfnt_off00010e5e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10E5E 16792 bytes