Malicious PDF — malware analysis report

Static analysis result for SHA-256 013c4fb53f5c4c3d…

MALICIOUS

PDF

85.9 KB Created: 2021-07-30 12:56:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4ae24bfb3df5646f09f6628ba93ee3ea SHA-1: 359a84d1081bdf6315eb7ed221746660c9294565 SHA-256: 013c4fb53f5c4c3decdace70939b5be103909ba71a1fecd97a0c3525bd02e705
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous external URIs and link farm patterns, suggesting it's designed to redirect users to potentially compromised websites or download further malicious content. The presence of embedded URLs and the 'link farm' heuristics indicate a strong intent to direct users to external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://krisoc.ru/uplcv?utm_term=ielts+writing+task+1+example+general
    • https://freshchannels.com/home/sites/freshchannels/public_html/ckfinder/userfiles/files/50290815716.pdf
    • http://ubest.ru/images/file/27632305853.pdf
    • https://theatresaucinema.fr/uploads/file/64054671671.pdf
    • https://amd-export.com/site/upload/file/nopajox.pdf
    • https://multimetrics.com/ckfinder/userfiles/files/99536069962.pdf
    • http://thebankcardservices.com/uploads/files/tudetevanoxun.pdf
    • https://www.emmabowman.com/wp-content/plugins/super-forms/uploads/php/files/3edff63a7e8ce25a57c34272eabb4f65/molijugetuvonafibip.pdf
    • http://xn--80aikni6a0b.xn--p1ai/images/file/xudorek.pdf
    • http://isgsrl.it/images/file/38347386807.pdf
    • http://english-island.pl/wp-content/plugins/super-forms/uploads/php/files/0io9prfldrht8jq4ppnaq1sgc1/rilenomavetamonivuwet.pdf
    • https://engineeredrepinc.com/wp-content/plugins/super-forms/uploads/php/files/08b9b7a2b2182fd71103fc123964760e/99015176066.pdf
    • http://orgue-chantepie.info/FCKeditor/upload/file/juxivevozobimo.pdf
    • https://iva-vietnam.com/userfiles/file/foxiwenedumixode.pdf
    • http://curry-box-deluxe.de/userfiles/file/53255185929.pdf
    • http://qazaqbanki.kz/data/content/files/46125799340.pdf
    • http://aberdeeneyes.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1606ca8d78b6cf---73484365770.pdf
    • https://angkoronetour.com/userfiles/file/89649134818.pdf
    • http://globeksa.com/ckfinder/userfiles/files/82858957879.pdf
    • https://grafitpoint.ru/wp-content/plugins/super-forms/uploads/php/files/348a349be5a57107d5d1bb63458dcc3c/pikujalinugofebakovo.pdf
    • http://zge-led.com/luodan/images/userfiles/file/nujelemenewujisudiwugon.pdf
    • http://vtvxm.vn/userfiles/file/tadifufa.pdf
    • http://winso.tw/userfiles/file/wowuxexuvozararenojesoga.pdf
    • http://senseoftourism.dk/userfiles/file/diteletimivetulolo.pdf
    • http://optimus.org.au/wp-content/plugins/formcraft/file-upload/server/content/files/160bc0249f1019---xifejibi.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_off0000ec93.bin
1d11907a0d8c4d6235dab2312b16bebf530c9a36a1acc920e3a1b95e0c07092f
pdf-font-stream PDF embedded font (sfnt) at offset 0xEC93 16824 bytes
font_01_sfnt_off0001189c.bin
37d02e168593eb80c44f8b336fdcbba4ba877dbc32bfdce4d56719aaf2a17d39
pdf-font-stream PDF embedded font (sfnt) at offset 0x1189C 10760 bytes
font_02_sfnt_off00013177.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13177 16792 bytes