Malicious PDF — malware analysis report

Static analysis result for SHA-256 810f3649087097de…

MALICIOUS

PDF

82.3 KB Created: 2021-09-22 17:44:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 99c4ee7b9b3cd09325bdaa2d3938aa8a SHA-1: 72de719ef41df5d1a8e0b2bd5fc05e272d075503 SHA-256: 810f3649087097de8fd4e394af649cb06cd1bd44d3e01b4e100be3771c077445
172 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample is a PDF containing embedded JavaScript and numerous external links, many of which point to potentially compromised websites or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The embedded JavaScript and link farm suggest an attempt to redirect the user to a malicious site or download a secondary payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 8

  • 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.
  • 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://sadhankendra.org/erc/media/ketixotenadatibo.pdf
    • https://myshalewell.com/userfiles/file/zosit.pdf
    • http://hanauhrova.cz/files/visutake.pdf
    • http://mawratanews.com/armedia/uploads/files/53657446584.pdf
    • https://tomaszbizon.pl/web/uploads/files/sixowixibarinopuj.pdf
    • http://emannsltd.com/userfiles/leximunubetojuvujuduxobev.pdf
    • http://adams-gold.ru/archive/image/file/detojisegesexaremunexewul.pdf
    • http://bearings-home.com/userfiles/file/sixikagijoxutizovaxas.pdf
    • https://www.pactforfamilies.org/ckfinder/userfiles/files/85876445117.pdf
    • http://hantechwelding.com/userfiles/file/2021090700264773499.pdf
    • https://bnbcostaverde.it/userfiles/file/vowefepumilis.pdf
    • https://razdolle.by/wp-content/plugins/super-forms/uploads/php/files/hi3aff4khbu94kpb6ng266knq3/15199102874.pdf
    • http://transchem-tech.com/Uploadfiles/files/23631488826.pdf
    • https://yidinfo.net/wp-content/plugins/super-forms/uploads/php/files/gslnoie7rbbp7rrkjqiekbtpi2/17666775637.pdf
    • http://dnepropress.net/files/file/dudamokumagebe.pdf
    • http://pokorny-podlahy.cz/UserFiles/File/zazim.pdf
    • https://registracijakoncar.com/webroot/js/ckfinder/userfiles/files/42289380093.pdf
    • https://greenways.at/userfiles/file/kapafaponuna.pdf
    • https://www.hadlowsecurityshutters.com/wp-content/plugins/super-forms/uploads/php/files/7b816dacd79cb7c2f1731c020dd61f5e/24437663047.pdf
    • http://zoekidsworld.com/userfiles/file/10486138950.pdf
    • http://hemeringen.de/ckeditor_ablage/userfiles/files/11024602309.pdf
    • http://tatugigo.com/ckfinder/userfiles/files/86370891782.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=download+game+subway+surfers+mod+apk+paris
    • 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_off0000da33.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDA33 16792 bytes
font_01_sfnt_off0000f245.bin
bc4b718a1a1603cdce11785ec69f4e68d141bb466634d6e1c94ce50596e2b016
pdf-font-stream PDF embedded font (sfnt) at offset 0xF245 17996 bytes
font_02_sfnt_off0001213a.bin
2745b3af4ce1b060f187d5acc1d0ee73865a0556f96020a1ecd239c88989c2f2
pdf-font-stream PDF embedded font (sfnt) at offset 0x1213A 11276 bytes