Malicious PDF — malware analysis report

Static analysis result for SHA-256 81b572bb0b944889…

MALICIOUS

PDF

84.9 KB Created: 2021-06-26 07:52:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1f1e61367490cb0b7caafb55c8164ef9 SHA-1: d27d77ee12374ebe0f84ae1e5b023fee18dcedf7 SHA-256: 81b572bb0b9448899230f362ce16465da7ed5edcdfaeeb714bc1ac164f9305b7
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file contains embedded JavaScript, which is a common technique for delivering malicious content. The heuristics indicate that the PDF acts as a link farm, directing users to numerous external URLs, many of which are hosted on compromised websites. The embedded JavaScript likely facilitates the redirection or further payload delivery, contributing to a phishing or malware distribution attack. The ClamAV detection and ML classifier strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://ketchas.ru/uplcv?utm_term=my+brother+my+brother+and+me+tv+show+streaming
    • http://festivaldeliteraturadepereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607cd620082db---46804234228.pdf
    • http://oryginalnedekoracje.pl/userfiles/file/puxorovenoteladifakebun.pdf
    • http://www.mvdisposal.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c0b64b006f4---roloduxewutulofetebelef.pdf
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/251632t60bqvt1aliob3n95f45/zunufavaruwe.pdf
    • https://big-cash.de/wp-content/plugins/super-forms/uploads/php/files/tqckj9q06msd501k1oqkbd58hb/ponevekagi.pdf
    • http://www.reroofingbrisbaneqld.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1608e16e541963---wadulosixamuwozunumibebi.pdf
    • https://homini.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1608ceb3c29d70---1229541548.pdf
    • https://winston-woodward.com/wp-content/plugins/super-forms/uploads/php/files/1daea96f29cd5974f6d1088658bace7d/6576077982.pdf
    • https://www.fifatravels.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609df4d8a64f0---bizuzuzakibipuda.pdf
    • http://asu.com.vn/wp-content/plugins/super-forms/uploads/php/files/3k47ls30tusl7u4l4kju15udvh/23931928161.pdf
    • https://atlastoursntravels.com/userfiles/file/xiriliforunodemonekosap.pdf
    • http://docando.es/js/ckfinder/userfiles/files/48117548713.pdf
    • http://primaneighbors.com/userimages/firebukunitupumir.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f1e1f58de7---77563433737.pdf
    • http://aftckwt.com/uploads/file/9086383219.pdf
    • https://goldengrowers.com/wp-content/plugins/super-forms/uploads/php/files/3bc8f06066d347a1d43bf5c7d5510105/kazitalumefinazex.pdf
    • http://muskogeeroughers1967.com/clients/9/98/9899c641331876fb313f08ec475a0443/File/sinixi.pdf
    • http://alemotta.com/resources/original/file/96471322528.pdf
    • https://tonwen.org/userfiles/file/rorivikerovomokesebali.pdf
    • https://forumhotel.by/wp-content/plugins/super-forms/uploads/php/files/fudkhps8bfjbre2k2osuojm672/taruze.pdf
    • http://hgbs.de/userfiles/file/84851187493.pdf
    • https://singaporeroadshow.com/wp-content/plugins/super-forms/uploads/php/files/7d7b1ceb3a162b81a439a5e9c05309f6/6270440753.pdf
    • https://ohligschlaeger-berger.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b2e1afd4e10---juxifem.pdf
    • https://finances-canada.com/wp-content/plugins/super-forms/uploads/php/files/c8ee77ce80cba818e5f0d305bbf35a2a/mukolewikepudalemun.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e508ed37fc---mosinigexubovezizumiwimi.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_off0000e6c3.bin
54d3233af5251650844f0ca0ca99ad9565b5e84b2ac7c89c9cb61b30035d59e7
pdf-font-stream PDF embedded font (sfnt) at offset 0xE6C3 11048 bytes
font_01_sfnt_off00010031.bin
69ad645c37c1c6b9ba6b975cd75954fbc7084473b7292c0c3df7ca06a92c0339
pdf-font-stream PDF embedded font (sfnt) at offset 0x10031 17480 bytes
font_02_sfnt_off00012dad.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12DAD 16792 bytes