Malicious PDF — malware analysis report

Static analysis result for SHA-256 3412772fb1828ded…

MALICIOUS

PDF

89.1 KB Created: 2021-10-10 13:03:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 602c3ac13dc1b0b479398b9635557837 SHA-1: d1a4a954435d343c441244f2d8449f7217bae8fc SHA-256: 3412772fb1828ded06defde58b79fcf8e86f7859b0f9aa4fcd56968a3506925a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm pointing to compromised CMS uploads and disposable hosting, with numerous external URIs. The document body is heavily obfuscated and contains binary data, suggesting it is not intended for direct user interaction but rather to host malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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://huntic.ru/uplcv?utm_term=rate+vs+concentration+graph+first+order
    • http://yule-sign.com/upload/editor/file/20210926161304.pdf
    • http://nieruchomosci-swidnica.pl/userfiles/file/88476299089.pdf
    • https://gesema.com/UserFiles/file/febudogurifu.pdf
    • https://rajakeempat.com/contents/files/68643089699.pdf
    • https://kede.org/userfiles/file/movikulolonugeborewopedib.pdf
    • http://flygarfield.net/userfiles/file/tikasogomewibizukesiwo.pdf
    • https://cananalimdar.com/wp-content/plugins/super-forms/uploads/php/files/fd4sqgd1802v334c76fsoune29/dilutoduxopevabumenevo.pdf
    • https://andymullinscommercial.com/home/andy/public_html/ckfinder/userfiles/files/xiginoni.pdf
    • http://gpszone.hu/upload/userfiles/file/89983761224.pdf
    • https://marblobathware.ph/app/webroot/img/files/pepajakabunugimij.pdf
    • https://ohligschlaeger-berger.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613ad7b8e415c---51852139526.pdf
    • http://studiovalentini.eu/userfiles/files/37793710041.pdf
    • https://laptoptranganh.com/data/dulieu/files/5394389812.pdf
    • https://tierrettung-in-katalonien.org/ckfinder/userfiles/files/majejedidulakorukudenat.pdf
    • http://wellgroup.cz/UserFiles/File/texoposogusoxes.pdf
    • https://www.smartfutureexpo.com/ckfinder/userfiles/files/xewabofez.pdf
    • http://vcelari.naceradec.cz/includes/ckfinder/userfiles/files/5054849685.pdf
    • http://go-pxl.com/uploads/files/dodikaluruvejaniwatekib.pdf
    • http://bjzjygj.com/fckeditor/editor/filemanager/connectors/php/userfiles/file/keletaferub.pdf
    • https://salwangurugram.com/files/pelafigusanuk.pdf
    • https://keralatemples.info/ckfinder/userfiles/files/majixojikemuzagobewawaxur.pdf
    • http://tiszaikaland.hu/upload/file/76210657523.pdf
    • https://bevasilicones.in/userfiles/file/4449383427.pdf
    • http://www.recetasyconsejos.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f3f6484e8a---87281781763.pdf
    • https://marlin-aquarium.ru/ckfinder/userfiles/files/gupovatilojelopupakebelu.pdf
    • http://cluster006.ovh.net/~greeters/namur/ckfinder/userfiles/files/54873715652.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_off0000eebe.bin
aa716f40df60996e7da58fa12bbf2ab7dfe471b58ec0cfabdbaae44c1c2cb436
pdf-font-stream PDF embedded font (sfnt) at offset 0xEEBE 20596 bytes
font_01_sfnt_off000124d2.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x124D2 16792 bytes
font_02_sfnt_off00013ce9.bin
f3a2f3126ba16a3d9e59f4246590dc5ec7048f842c75c724c2d71a737455c97e
pdf-font-stream PDF embedded font (sfnt) at offset 0x13CE9 10964 bytes