Malicious PDF — malware analysis report

Static analysis result for SHA-256 a0031d4583238ca5…

MALICIOUS

PDF

76.2 KB Created: 2021-09-17 12:47:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 9e06ce37060ba527c78a15a0ccc080c4 SHA-1: ab7e5db443c83b3a0ab4ec8bab23aac16abfeab7 SHA-256: a0031d4583238ca51c613a285e09ec7055e4f133a096c55774072f29e4100767
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The presence of embedded JavaScript and numerous external URIs, many pointing to compromised WordPress sites or link farms, suggests it's designed to redirect users to potentially harmful content. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' specifically indicates the document's structure is a link farm on disposable hosting, likely for SEO manipulation or phishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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://laborke.ru/uplcv?utm_term=free+fire+apk+download+new+update+2021
    • https://artsketch.ru/wp-content/plugins/super-forms/uploads/php/files/b2393c4e7ce4eeec1d9c723292646c72/fajezufesakemipover.pdf
    • https://snoman.mb.ca/ckfinder/userfiles/files/xasoxevuwaxemafab.pdf
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/e12eikgq4ppbblghe2tm250063/13108902641.pdf
    • https://noks.cz/wp-content/plugins/formcraft/file-upload/server/content/files/161347c0bb8bbe---11244841345.pdf
    • http://www.ktgroup.co.uk/ckfinder/userfiles/files/pipoga.pdf
    • http://moscreen.in/cmsfiles/file/fimuximazawefomijasewezoj.pdf
    • https://projetovm.com/uploads/files/2682661739.pdf
    • http://www.pointcookelectrician.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161411152da538---80095935956.pdf
    • https://www.tessilgiada.it/wp-content/plugins/formcraft/file-upload/server/content/files/16135e7eb4def3---gafowavigivojija.pdf
    • http://www.tempshift.com/app/webroot/files/uploadimagesfile/96215316491.pdf
    • http://bubb.cn/up_file/file/diberudububixeziwozes.pdf
    • http://htbestcomputer.com/media/ftp/file/meluvegepaxefekolome.pdf
    • http://taketty.xyz/js/ckfinder/userfiles/files/wisipakaku.pdf
    • http://medicapoland.pl/uploaded/file/newuzarimabimezotiwowol.pdf
    • http://elandtour.com/FileData/ckfinder/files/20210905_47BCBEF79995C6CC.pdf
    • http://www.gesas.it/media/mailinglist/file/33309375238.pdf
    • http://tantusmarina.com/UserFiles/file/sazaxunux.pdf
    • http://gandolfiarchitetti.com/userfiles/files/nufuvuzasukuju.pdf
    • http://kmbb.at/userfiles/file/mafopuwofefamujosijep.pdf
    • https://nexapos.com/upload/files/41543796940.pdf
    • https://www.mclarenpress.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e52bde8b18---dereber.pdf
    • http://www.cerathai.com/image/upload/File/nuniz.pdf
    • https://nhatngudongkinh.phapluatvietnam.com/upload/ckupload/files/tamawoposaxuvi.pdf
    • https://lnpro.in/ckfinder/userfiles/files/53239145995.pdf
    • http://vanprodukt.cz/UserFiles/File/zekem.pdf
    • http://bsp-plovdiv.org/ckfinder/userfiles/files/wimodasujajidafujonetepo.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_off0000c74d.bin
ee2f95e5d424397f7b46b66ea319a7e10632d5c5a216e0d9347a52a1c0358b32
pdf-font-stream PDF embedded font (sfnt) at offset 0xC74D 10872 bytes
font_01_sfnt_off0000e094.bin
c2b3ba4788c86c3bd3372cae4b8901c1c710a02e082ee7300fde2c95bf073d64
pdf-font-stream PDF embedded font (sfnt) at offset 0xE094 16648 bytes
font_02_sfnt_off00010b52.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10B52 16792 bytes