Malicious PDF — malware analysis report

Static analysis result for SHA-256 5bae24ac6bec1f19…

MALICIOUS

PDF

71.8 KB Created: 2021-09-29 13:26:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: a899624680f1209824f655261b0605be SHA-1: c824467c8901a559cdcc012cb223647adb30568c SHA-256: 5bae24ac6bec1f19231ced0d330bb3f04e8995d38ebc0a9a008f1d1683d0e2f3
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. The heuristic 'SE_CALLBACK_LURE' strongly suggests a callback phishing or tech-support scam pattern, where the document prompts the user to call a phone number. While no scripts were extracted, the presence of numerous external URLs, many pointing to PDF files on compromised or disposable hosting, suggests a multi-stage attack or a link farm designed to redirect users to malicious content. The document's metadata indicates it was generated by wkhtmltopdf, a tool often used to create PDFs from web content, which can be leveraged for phishing lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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://smidgel.ru/uplcv?utm_term=principles+of+accounting+exam+questions+and+answers+pdf PDF link annotation
    • http://mmsmarin.com/imgimage/file/65161365673.pdfIn PDF document text
    • http://bigdoughpizza.com/uploads/files/nasuza.pdfIn PDF document text
    • http://apexnepaltravel.com/userfiles/file/59392582332.pdfIn PDF document text
    • http://www.iso-clean.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16150de44aa94a---86224191440.pdfIn PDF document text
    • http://www.stratcareerservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/161515a0513cdf---11246178702.pdfIn PDF document text
    • https://la-klamm.org/Files/files/wagigoratanavetojawisavok.pdfIn PDF document text
    • http://andreuma.madteam.net/ckfinder/userfiles/files/24326600074.pdfIn PDF document text
    • http://hanstime.com/userData/board/file/lobovit.pdfIn PDF document text
    • http://veszpremlizards.hu/_user/file/32522489110.pdfIn PDF document text
    • http://podhoru.cz/userfiles/file/razar.pdfIn PDF document text
    • https://schmitz.cz/res/file/60055849463.pdfIn PDF document text
    • http://s-pack.kr/userfiles/file/20210923102918.pdfIn PDF document text
    • http://www.premiumimport.nl/ckfinder/userfiles/files/29822656668.pdfIn PDF document text
    • http://oroblupiscine.it/userfiles/files/51104309107.pdfIn PDF document text
    • https://tuabogadoangel.com/wp-content/plugins/super-forms/uploads/php/files/1aee27847242c7363f0896b63b3468c0/94926128166.pdfIn PDF document text
    • http://hillsdalehorseboarding.com/ckfinder/userfiles/files/81991606424.pdfIn PDF document text
    • https://izyskately.ru/foto/ck/files/4777344353.pdfIn PDF document text
    • https://mt-creativestudio.com/ckfinder/userfiles/files/92772091638.pdfIn PDF document text
    • http://minerva-collection.net/files/files/19496754641.pdfIn PDF document text
    • http://yoga-privates.com/yoga-privates/file/vovake.pdfIn PDF document text
    • https://jiu-hang.com/upfiles/editor/files/tujoniwabijisixelutig.pdfIn PDF document text
    • http://pansophers.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140235dc714a---giloluvowutur.pdfIn PDF document text
    • http://woodbridgeabw.com/uploads/files/58819418318.pdfIn PDF document text
    • https://marlschuz.com/userfiles/files/64557381798.pdfIn PDF document text
    • http://wine-paraphernalia.com/files/winep/_repo/file/mafimufokuzotorin.pdfIn PDF document text
    • 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_off0000b482.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB482 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cc99.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC99 11400 bytes
SHA-256: 75675cafe4a09ef524c91ee16f364995394c0b7b38536861c1c355952ff88306
font_02_sfnt_off0000e701.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE701 16368 bytes
SHA-256: 6acb206b5b686eedbe17a72835d8dc1a418a2016d68a02109578f08c5600efb3

Open this report in the interactive analyzer, or submit your own file for analysis.