Malicious PDF — malware analysis report

Static analysis result for SHA-256 591a40bd0871cacf…

MALICIOUS

PDF

82.5 KB Created: 2021-07-01 18:27:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d0be87dcef5aa4733092e778cc03c746 SHA-1: 99079082d284abc8458f4295bb7e92c2d69dcfa6 SHA-256: 591a40bd0871cacfb34cd3f25802cd68bdcca92aa3e8929a2c9edb296df3fcfa
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics as malicious, including a high-severity PDF_RANDOM_URL_LINK and ML_NYX_PDF_MALICIOUS. It contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable domains, suggesting a link farm designed to redirect users to malicious content. The ClamAV detection further confirms its malicious nature, identifying it as Pdf.Phishing.Trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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 http://nowator-zpu.pl/userfiles/file/topibimuwenimox.pdf
    • https://k-kompany.ru/wp-content/plugins/super-forms/uploads/php/files/6ba6113501034d9375a28540dc444f92/47745674981.pdf
    • http://xn--b1ahhafccpgkb2bxo.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/aa43534deffaa68e2ea63d9619b7c893/wobakovazesulewati.pdf
    • http://sahamit.net/userfiles/file/jexoxatodulinesazus.pdf
    • https://zzarosiscarampola.it/file/barodutajalojan.pdf
    • http://ural-kip.ru/admin/ckfinder/userfiles/files/59097348294.pdf
    • https://agroadvanced.com/app/webroot/newsletters/editor/files/44985601539.pdf
    • https://adbetelparaguay.com/wp-content/plugins/super-forms/uploads/php/files/7723b958f4f79963c1ffe88f8ef2372e/wexovujadizapatamopamax.pdf
    • http://adhdadvisory.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073c566b1829---53809694028.pdf
    • http://xoblates.com/clients/e/e0/e08cfb93fb97b00c28394d0532709dc9/File/22159103381.pdf
    • https://optimustelecoms.com/ckfinder/userfiles/files/53223586874.pdf
    • https://www.harnoordesigns.com/wp-content/plugins/super-forms/uploads/php/files/e81cpnc1fc0bhl57vsid29l542/43484749882.pdf
    • http://w-f-l.de/user_img/file/56336868124.pdf
    • https://deepankarbasu.com/FCKeditor/file/70670089862.pdf
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160716ac087d6f---64737785923.pdf
    • https://festival.bg/fckeditorfiles/file/86058830844.pdf
    • https://damsindia.org/admin/uploads/file/folunowelubitew.pdf
    • https://theshairpodcast.com/wp-content/plugins/super-forms/uploads/php/files/c05206e2ccd7916cdb8c307fc82448f7/55713731210.pdf
    • http://www.atrium-tuiles.com/wp-content/plugins/formcraft/file-upload/server/content/files/160751747d74c3---begeridifeme.pdf
    • https://www.peeryhotel.com/wp-content/plugins/super-forms/uploads/php/files/1078f6619e3a7c661c61c7f5e0167bc3/83434494566.pdf
    • http://khodahoanglang.com/admin/webroot/upload/image/files/23363874847.pdf
    • https://childrencareandliteracysociety.org/userfiles/files/nasavegemiduwupavofunux.pdf
    • http://xn--b1ahhafccpgkb2bxo.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/5bc18539b7e2be42dc5bb5954fbd7580/newerenawoledakotaropof.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=electricity+and+magnetism+study+guide
    • 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_off0000dfa7.bin
dfe5beb84cad4d5a00c6d84436323a3238141e61df9a6a38380af8f61b8b9b6b
pdf-font-stream PDF embedded font (sfnt) at offset 0xDFA7 16864 bytes
font_01_sfnt_off00010bc9.bin
235292cccf848ef04e4ed1eca6a9ce90b347a28973c1ce4adab490a0e574479c
pdf-font-stream PDF embedded font (sfnt) at offset 0x10BC9 10788 bytes
font_02_sfnt_off00012467.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12467 16792 bytes