Malicious PDF — malware analysis report

Static analysis result for SHA-256 05b21e8edf76e164…

MALICIOUS

PDF

84.4 KB Created: 2021-07-31 20:59:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 3e812f95bd175b618f3348b5b5374ce7 SHA-1: 951f4e227b31148cfaf9913f232bbe76eb9cadd0 SHA-256: 05b21e8edf76e164c8db4b41cd408a748e448bf83403bf37cc419944a59e79f0
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable domains, indicating a link farm for malicious redirection. The ML classifier and ClamAV detection strongly suggest malicious intent. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a phishing or malware distribution attempt, likely leveraging spearphishing attachments as the initial access vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://c2r-auto.com/uploadfiles/file/2021053014382873499.pdf
    • http://ambulatorioveterinariosantanna.eu/userfiles/files/gimetefuwadapejonodina.pdf
    • http://carneslaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/70546858997.pdf
    • https://g3az.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f929063f14---bokoje.pdf
    • https://comobrew.com/newsite/images/user_uploads/file/50539799861.pdf
    • https://medsplus.us/admin/images/file/razotiruwetimagutakabalij.pdf
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609d3d7c755d9---wowosajemib.pdf
    • https://too.kg/wp-content/plugins/super-forms/uploads/php/files/3ab7b58eb161ef1c0858a4f1ca0b99c6/76382082790.pdf
    • http://etasystem.net/userfiles/files/visenapane.pdf
    • http://bsa.by/ckfinder/userfiles/files/fiwukosejewome.pdf
    • http://studioguidobarbieri.it/userfiles/files/sinerunitidedal.pdf
    • https://www.lipfish.no/wp-content/plugins/formcraft/file-upload/server/content/files/1606c93b04eb6d---furuwibaw.pdf
    • https://thetitangroup.ca/wp-content/plugins/super-forms/uploads/php/files/4f89dfac97754fa3d6b5f79e6539ab46/kumurekodozi.pdf
    • http://rogo-rotterdam.nl/files/purixew.pdf
    • http://recruiters-zone.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098d200cdb76---63171311829.pdf
    • https://directprocessors.com/wp-content/plugins/formcraft/file-upload/server/content/files/160952475bc7b2---volejezurutisafamogubo.pdf
    • https://weeb.nu/userfiles/file/76279213447.pdf
    • https://hmv.ir/wp-content/plugins/formcraft/file-upload/server/content/files/160e2844936128---40592408799.pdf
    • http://topoint.cc/userfiles/fckFile/20210728053830.pdf
    • https://www.blackandwhite-salon.com/wp-content/plugins/super-forms/uploads/php/files/8b7c222675d079833bdef2ad8aca444c/99439335700.pdf
    • http://tavernadelsnoguers.com/wp-content/plugins/super-forms/uploads/php/files/4018238190254668b30f91986019c814/guwapuromunuko.pdf
    • http://studiomistretta.com/userfiles/files/33041868319.pdf
    • https://hacunamatata.ru/wp-content/plugins/super-forms/uploads/php/files/21c326fefca73e55932e35c47f1ddba2/46826460695.pdf
    • http://embeddedhr.com/ckfinder/userfiles/files/19812032741.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=ghanaian+choral+music+scores+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_off0000e4ab.bin
9c010d89780f72d863835495488a116923aa7244c2656afdebf935bb3924d2d4
pdf-font-stream PDF embedded font (sfnt) at offset 0xE4AB 17536 bytes
font_01_sfnt_off00011261.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11261 16792 bytes
font_02_sfnt_off00012a78.bin
8ffcaad50585a3666e6fa842ba034a4b2eb8e146927a8e902c1d6431c9d186bf
pdf-font-stream PDF embedded font (sfnt) at offset 0x12A78 10928 bytes