Malicious PDF — malware analysis report

Static analysis result for SHA-256 87421a6870f64c2b…

MALICIOUS

PDF

86.5 KB Created: 2021-07-05 19:19:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0a2f29d3a35df1cad0c4ca123382117b SHA-1: 09feb7feb598f484c46f642e3b7ed86ae7e89a98 SHA-256: 87421a6870f64c2b4e923b651223bb4964e8fb761b9bea2211fd63ca8b83bec5
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to compromised WordPress upload directories and disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly support its malicious nature. No scripts were extracted, but the structure and URL patterns are indicative of a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://coretry.ru/uplcv?utm_term=the+maze+runner+list+of+movies
    • https://dusunceokulu.net/resimler/files/86847317133.pdf
    • https://melz-feu.ru/upload/lonovud.pdf
    • http://marcelponjee.nl/ponjeefiles/file/19394933454.pdf
    • http://mognational.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071b4023362f---mizubusodewuvabizutog.pdf
    • http://aberdeeneyes.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16072eb7bd7220---dotiwefonewurot.pdf
    • https://donnasalon.ru/wp-content/plugins/super-forms/uploads/php/files/c0476262880a0bfc067c45c6000a5507/57906845294.pdf
    • http://bong-dem-long.org/upload/editor/files/20668002307.pdf
    • http://jiehuist.com/userfiles/files/36491295052.pdf
    • http://szao-spb.ru/images/news/file/dubevuripuxur.pdf
    • http://www.misshandicap.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160bfb7d0e555e---38037343100.pdf
    • http://ecompletecontact.com/ckfinder/userfiles/files/34275524263.pdf
    • http://www.northeastmarquees.com/wp-content/plugins/super-forms/uploads/php/files/14d060c11583acbcbb11e59da6442664/dasorazekasage.pdf
    • https://acronimocostanzo.com/userfiles/file/9097898132.pdf
    • https://cualuoihoanmy.com/uploads/userfiles/file/54413717650.pdf
    • https://kamber.dk/wp-content/plugins/super-forms/uploads/php/files/1038f91b00f7750807689bde214141c7/xakowunukowalan.pdf
    • http://averon.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1609cfd28ce71d---63653758178.pdf
    • https://www.sir.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160ae0a49aebfd---fuditagizujimesofopogibax.pdf
    • http://alpha-cp.com/userfiles/file/nivenizebebeg.pdf
    • https://www.skyline-recruiting.com/wp-content/plugins/super-forms/uploads/php/files/43baed20cb9e86fb6f64fbb87643849b/93187462116.pdf
    • http://www.colegiometa.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/160c116948ba1c---topumopevudigajobowebex.pdf
    • http://hyperasp.net/userfiles/file/74360670830.pdf
    • http://jilienjrubin.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/tudewe.pdf
    • https://inchiriereelicopterromania.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160e1fbadb4eaa---navenalewapuvamizelozex.pdf
    • http://burfel.ru/upfiles/files/18185643229.pdf
    • http://e1pl2.nazwa.pl/busy/fotki/file/xexomumiwusupilurazar.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_off0000edde.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEDDE 16792 bytes
font_01_sfnt_off000105f5.bin
104b2c6f22aa033f8c730116094db717404d1fe21380ada6a7f908b16779d90a
pdf-font-stream PDF embedded font (sfnt) at offset 0x105F5 10668 bytes
font_02_sfnt_off00011e41.bin
ad69ad729a73ae0d9a231e4d46cf73ab285685bf10d390db7be6bf5c4081847e
pdf-font-stream PDF embedded font (sfnt) at offset 0x11E41 17548 bytes