Malicious PDF — malware analysis report

Static analysis result for SHA-256 751917b232c741f6…

MALICIOUS

PDF

81.4 KB Created: 2021-09-15 22:56:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5d7609c5cd098b1e1490a9c69d39a5e4 SHA-1: d74edf5758aef48169bf2d8ad769c055c8a2e2e7 SHA-256: 751917b232c741f626e093e9ead0fae46a23d1974f59234c66d83928fcd80c47
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous external links, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The PDF structure and embedded links are consistent with phishing or malware distribution campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://krisoc.ru/uplcv?utm_term=chrome+turn+off+night+mode
    • http://embody.box8websites.com/ckfinder/userfiles/files/sidibebonume.pdf
    • http://makrostal.pl/user_images/file/15152670059.pdf
    • https://petroblend.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a817ba3180---66997673332.pdf
    • https://cottingham-group.com/cufiles/files/tumapimekezi.pdf
    • https://rizecanreklam.com/images/file/11996585670.pdf
    • https://www.cocochan.com.pk/wp-content/plugins/super-forms/uploads/php/files/ea0dba8966e95cff1689a14ff15446e1/35635273866.pdf
    • http://i-tos.com/userData/board/file/valukuxisusefijat.pdf
    • http://an-ocn.ru/ckfinder/userfiles/files/28283074502.pdf
    • http://galantemontagnana.it/ckfinder/userfiles/files/bowubowidamitumivapubu.pdf
    • https://gamepinleri.net/calisma2/files/uploads/kinenelipuxunokemata.pdf
    • http://kaus21.com/userData/board/file/dabijesezafojubelonevibib.pdf
    • http://coumert.com/images/file/dubamuvanag.pdf
    • https://demetraproject.eu/ckfinder/userfiles/files/mudemunujunugez.pdf
    • https://dadesigning.com/daduserfiles/files/xemezajusikunono.pdf
    • http://dharmapuridiocese.com/svnprojects/DHD/Source/images/files/rerudijapanon.pdf
    • http://sun-apartments.pl/data/pages/90248250614.pdf
    • https://fsbulletsandbrass.com/userfiles/files/3175484288.pdf
    • http://phone-server.com/userfiles/file/relibujefowexago.pdf
    • http://melly-incendie.fr/img_db/bemewizijiwitovataloda.pdf
    • http://aaaexpressheating.com/userfiles/file/47506916510.pdf
    • https://sdyh.gr/wp-content/plugins/super-forms/uploads/php/files/mbr2ta2mjvaijtae16if3jv734/76924895029.pdf
    • http://canadianartistic.com/userfiles/file/14645651789.pdf
    • http://futureinfashion.com/ckfinder/userfiles/files/vutiz.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_off0000da05.bin
87af997eeabf5e7975ed39a51e5ef582b750b331ef95f58738e161e4ccdea426
pdf-font-stream PDF embedded font (sfnt) at offset 0xDA05 18136 bytes
font_01_sfnt_off000108a7.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x108A7 16792 bytes
font_02_sfnt_off000120be.bin
92483e987fde707b84d57ae159efa0e6bf982a29d6885fef514ac0cd07659e99
pdf-font-stream PDF embedded font (sfnt) at offset 0x120BE 10556 bytes