Malicious PDF — malware analysis report

Static analysis result for SHA-256 f5cc455c72aed2f0…

MALICIOUS

PDF

70.4 KB Created: 2021-09-07 09:56:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: d13ac53d55d4fa0974ba990afd710921 SHA-1: 2319b91db8d8556eebce25866304398fd5ab1e81 SHA-256: f5cc455c72aed2f09738ac29ff020cbc9ce98c3bdf774f67209a551c7e55670e
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress sites and other disposable hosting, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery via these links. No scripts were extracted, and the document body was unreadable, so the attack pattern is inferred from the URL analysis and heuristic firings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 http://koyomisushi.com/uploads/files/zapit.pdf In PDF document text
    • https://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/01f06e4ad7a626f493d9d9b54a3452c5/begejejokazoxeju.pdfIn PDF document text
    • https://tsegypt.com/file/7743598732.pdfIn PDF document text
    • https://brunoamaranti.it/wp-content/plugins/super-forms/uploads/php/files/3d04vhm7pi111vmcs5urg7dc07/zefadefi.pdfIn PDF document text
    • https://comfortinnbarrie.com/phpsites/vertical_living/uploads/file/dejawukumalosefebulebis.pdfIn PDF document text
    • http://pmdrecycling.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082f14905dba---43993808752.pdfIn PDF document text
    • http://intestinalfortitude.org/clients/0/0c/0cf504f131cb0201443a7bd449519f4a/File/rikojofekewepobijipev.pdfIn PDF document text
    • https://upbilbao.com/ckfinder/userfiles/files/67076201209.pdfIn PDF document text
    • http://ekhoron21.mn/uploads/files/satulaborobajimafutemuvax.pdfIn PDF document text
    • http://bagumul.com/file_upload/spaw_upload/file/20210623043335.pdfIn PDF document text
    • http://kapalishakti.com/ckfinder/userfiles/files/43206360268.pdfIn PDF document text
    • http://hnc2.com/userfiles/file/rotisup.pdfIn PDF document text
    • http://erpsamik.com/ckfinder/userfiles/files/fomijan.pdfIn PDF document text
    • https://cashofferoregon.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c57b47d8e51---11534016720.pdfIn PDF document text
    • https://nileagriculturalindustries.com/file/75477115757.pdfIn PDF document text
    • https://www.heainc.com/wp-content/plugins/formcraft/file-upload/server/content/files/16123f538d6b70---54693518479.pdfIn PDF document text
    • https://sitebyside.ru/wp-content/plugins/super-forms/uploads/php/files/626a6b62155c0866ee6e2897b8f86f77/jatifakufe.pdfIn PDF document text
    • http://maroba-zirndorf.de/file/21507045363.pdfIn PDF document text
    • https://cristiandellavedova.com/wp-content/plugins/super-forms/uploads/php/files/v46at1kb4fbg5ghdsgk37esrv3/70305993552.pdfIn PDF document text
    • http://slowjamsundays.com/wp-content/plugins/formcraft/file-upload/server/content/files/16123943e97133---divafonudidos.pdfIn PDF document text
    • http://www.dogwoodagility.nl/ckfinder/userfiles/files/48664252984.pdfIn PDF document text
    • https://athensviptour.com/wp-content/plugins/super-forms/uploads/php/files/bd6424a01a2cb06f00746c80cbfe0d21/wivotaxil.pdfIn PDF document text
    • http://gld-lining.com/user_img/files/78737999033.pdfIn PDF document text
    • http://shengyaweb.com/uploadfile/file/2021081213425760.pdfIn PDF document text
    • http://otczenacts.com/media/files/56641068133.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=onix+mobile+phone+manualPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b563.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB563 15544 bytes
SHA-256: 8ceab623341f035f86f4d6d601c81bde9933f467c2a8dd5877e0b334972af8ad
font_01_sfnt_off0000dcf0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCF0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f507.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF507 10516 bytes
SHA-256: 473baf4a0af8a5147b6fb7155b292e41470fd41f48b2f2682b750fb5845b14ad