Malicious PDF — malware analysis report

Static analysis result for SHA-256 53a91e6f097af70a…

MALICIOUS

PDF

92.2 KB Created: 2021-09-16 22:37:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 31aa3460e3632405db9a4ddb0b03ae36 SHA-1: cfd616bdc59ff664c2c1e171b63ad1263321b188 SHA-256: 53a91e6f097af70a63d0fe57fa17ed94440332a032eae2d1b1f19dd9f103f69e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with many URLs pointing to potentially compromised or disposable hosting. The presence of numerous links, including those on compromised CMS upload storage, suggests an attempt to direct users to malicious content, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9970

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://ddtoyz.com/ckfinder/userfiles/files/88271880691.pdf
    • https://girilawfirm.com/content_files/files/laluxudularotefawogi.pdf
    • http://uitetenindex.nl/images/uploads/36408733218.pdf
    • https://www.bluegreenshouseboats.in/wp-content/plugins/formcraft/file-upload/server/content/files/161346fa22f289---sigufubizuwefu.pdf
    • https://etest.vn/app/webroot/uploads/files/lawizekunekudokegamif.pdf
    • http://www.childofafrica.org/media/userfiles/file/7116738993.pdf
    • https://morganmethod.tuesdaytrader.com/ci/userfiles/files/37804073880.pdf
    • https://umutfm.com/resimler/files/96339726218.pdf
    • http://kapsalonvogue.nl/files/file/misufakibotibekopoginim.pdf
    • http://ciaomamma.hu/editor_up/62641083683.pdf
    • http://visualpaint.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141b79ee233f---25987076343.pdf
    • http://tinhdaurosa.com/Images_upload/files/kinelipuwele.pdf
    • http://dh-cell.com/ckfinder/userfiles/files/92148913086.pdf
    • http://vitacanes.com/uploads/files/vebedijeneveda.pdf
    • https://dacinsara.ro/fckfiles/file/90388778456.pdf
    • http://e-skala.pl/userfiles/file/jawup.pdf
    • https://deepex.hu/hirek/files/12375551034.pdf
    • http://www.gpe-el.pro/ckfinder/userfiles/files/89507119596.pdf
    • http://fongyoskert.hu/userfiles/files/suziduse.pdf
    • https://sandp-engineering.com/ckfinder/userfiles/files/jetob.pdf
    • https://semsaesp.com/ckfinder/userfiles/files/80849174550.pdf
    • http://zsmnowakowski.pl/userfiles/file/22756802514.pdf
    • http://csc0516.com/userfiles/file/20210910113428_x03y18.pdf
    • https://rjiminfra.com/wp-content/plugins/super-forms/uploads/php/files/edce1b5423184f36afbbcaac1aa36ad7/57419726325.pdf
    • http://www.centralperdana.com/file/jigafiwawoxifitomasolalom.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=advanced+quantum+mechanics+book+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_off0000fb60.bin
2222a66d129d3ee9e999e0cd3d344e093345dc115f1063963130ee715ca678ff
pdf-font-stream PDF embedded font (sfnt) at offset 0xFB60 11264 bytes
font_01_sfnt_off0001153e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1153E 16792 bytes
font_02_sfnt_off00012d50.bin
2d6952f4d32388c9dfb07e266b5bdb7ad6cdf122a5bb1a92dd5cc2cda1f71e4f
pdf-font-stream PDF embedded font (sfnt) at offset 0x12D50 20216 bytes