Malicious PDF — malware analysis report

Static analysis result for SHA-256 73cd3fa5ba122924…

MALICIOUS

PDF

91.1 KB Created: 2021-09-17 03:50:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a6fc5ecb640453a3d7332321b8d50fff SHA-1: af28172ddd91539c7fb32fe6d0ab30b4a439726c SHA-256: 73cd3fa5ba1229247cbb8e4de38022308ab2f9258504202189edaa1b7d20d02f
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to disposable hosting or compromised sites, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. The embedded JavaScript is likely used to facilitate the redirection or exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 7

  • 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.
  • 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 http://delve-cr.com/uploads/95322910525.pdf
    • https://helicopterleasingservices.com/userfiles/files/22895792217.pdf
    • https://clinicscrm.com/img/files/33472578995.pdf
    • https://bangvetthuong.com/luutru/files/xitujarevox.pdf
    • http://dulwichtaxi.com/survey/userfiles/files/6953423095.pdf
    • https://noble-program.site/js/ckfinder/userfiles/files/72139069278.pdf
    • https://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/524c23a5a3e8cd5971bda6f82a1b417f/dagakidaluliduruvaxapo.pdf
    • http://italiangreyhound.pl/img1/userfiles/file/41797160379.pdf
    • http://naphotelbangkok.com/userfiles/files/48056347826.pdf
    • https://klcmekatronik.com/ckfinder/userfiles/files/2338465717.pdf
    • http://sweed-trans.eu/ckfinder/userfiles/files/rineta.pdf
    • https://marksiegeldds.com/wp-content/plugins/super-forms/uploads/php/files/df8747451c1442a6a0cbed618c9de221/fizegavijuxiwenetukud.pdf
    • https://turkuazhost.com/calisma2/files/uploads/80822397280.pdf
    • http://minhtoangalaxyhotel.vn/app/webroot/files/ckfinder/files/63823042705.pdf
    • http://maxgear.cz/webpagebuilder/ckfinder/userfiles/files/1749023852.pdf
    • http://fisioterapiasuzzara.it/userfiles/files/58312360381.pdf
    • https://eliteswimmingpoolsinc.com/wp-content/plugins/super-forms/uploads/php/files/ro6f3qt3b8ev2fnvlfekktgbs0/15039985711.pdf
    • http://anninh247.info/upload/files/84701570046.pdf
    • https://eliteplacementagency.com/uploads/files/xurunajibalatujiloso.pdf
    • http://hoadon-dientu.net/images/files/minemototivakaw.pdf
    • http://masan315.net/board/imagefile/file/36147132514.pdf
    • http://jiji.pgo.tw/pic/uploads/files/17764169516.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=a+quiet+place+2+watch+online+full+movie
    • 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_off00010060.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10060 16792 bytes
font_01_sfnt_off00011877.bin
6bc86a697fb27c01c9f7a2224ee8f254c5f802615a7322f12f91227453afb2f9
pdf-font-stream PDF embedded font (sfnt) at offset 0x11877 10976 bytes
font_02_sfnt_off000131e2.bin
be97013d282b0bebd62f56b35644292839fbddbf58451f811bd04355559abb48
pdf-font-stream PDF embedded font (sfnt) at offset 0x131E2 17620 bytes