Malicious PDF — malware analysis report

Static analysis result for SHA-256 ab4df2a7c6850a54…

MALICIOUS

PDF

81.1 KB Created: 2021-09-15 12:30:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c5eb708edd554921bbeb3c9c095daeb7 SHA-1: 4ac2e0ce7f51cb9111fec84112fce4bd0fe8b1b2 SHA-256: ab4df2a7c6850a54f0f1fda9b074bc89fe0f921fda6234c8c4d4365c2af0db42
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which are hosted on disposable domains or compromised WordPress sites, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to host malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

Heuristics 6

  • 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.
  • 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://catamma.ru/uplcv?utm_term=best+car+game+on+play+store
    • http://rayer.cn/d/files/3191530010.pdf
    • https://printjet.pl/pliki_user/File/sexilelisope.pdf
    • http://escrima-rlp.de/userfiles/file/podin.pdf
    • http://co-wemart.com/careeruserfiles/file/jekonoditajatexononogelox.pdf
    • http://unseretochter.ch/images/file/divimeverof.pdf
    • https://www.nstoplana.rs/ckfinder/userfiles/files/pokikevirukad.pdf
    • https://eownauto.com/uploadpic/files/zezovi.pdf
    • http://matstravel.ru/userfiles/file/99251877403.pdf
    • http://xn--or3bo5mvlb.com/data/editor/file/48874160760.pdf
    • http://bantinnhadat.com/users/files/kelikobavelawujunogavi.pdf
    • https://santa.my/images/users/00000000/files/darimizijaj.pdf
    • http://mcdanielz.eu/files/file/gibosezejabixegewaxefim.pdf
    • https://xn--1--8kcai1ck2bs.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/e01558c78232b3a91e6529459d12a7f4/mudizivasife.pdf
    • http://hatowo.com/app/webroot/uploads/files/gitid.pdf
    • https://koltoztetes-szallitas-lomtalanitas.com/ckfinder/userfiles/files/lajenilanatob.pdf
    • http://cyc.cz/pictures/clanky/files/wowebibiwim.pdf
    • http://sewakendragroup.com/userfiles/file/ruzosiwegiduliduzif.pdf
    • https://alismobile.co.uk/wp-content/plugins/super-forms/uploads/php/files/dfa267d72e2549483b6ccaed4b0da2b6/jurixudi.pdf
    • http://www.jokilaaksonratsastajat.fi/file/tojuti.pdf
    • https://redac.ch/upload/sejigeb.pdf
    • https://master.plus/wp-content/plugins/super-forms/uploads/php/files/fb7bf4d0f45ead1edaf3153a9a296221/xofeponanowilunogoro.pdf
    • http://4darchitecture.org/img/all/10860451420.pdf
    • http://www.ponderosafestival.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f1f8980a26---10510812318.pdf
    • https://houstoncoinshow.org/FCKeditor/file/37861319538.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_off0000d6f2.bin
8c620f7a8cf4d2913a1a66d291ae7020473e2bd9b7dbe9ebc5e09100a543952a
pdf-font-stream PDF embedded font (sfnt) at offset 0xD6F2 10792 bytes
font_01_sfnt_off0000efe9.bin
c4eba1bda3d34f595094a80c48d0f318d0162781ef279bf9471e8beeaf878acc
pdf-font-stream PDF embedded font (sfnt) at offset 0xEFE9 17956 bytes
font_02_sfnt_off00011eff.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11EFF 16792 bytes