Malicious PDF — malware analysis report

Static analysis result for SHA-256 3c9562bf13c6c3c0…

MALICIOUS

PDF

83.9 KB Created: 2021-09-01 09:26:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a08d2e1e6be1b34c92d2f75b90c3803b SHA-1: f962d541523ae3f4425f2346fb98fc2342f7e1b7 SHA-256: 3c9562bf13c6c3c0603055f371c4344cf90521e612ee80f7d50ccd24d0ddd331
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload storage or disposable hosting, indicative of a link farm designed to distribute malicious content or phish users. The ClamAV detection as 'Pdf.Phishing.Trojan' and the ML classifier's high confidence score further support a malicious classification. While no scripts were explicitly extracted, the nature of the embedded URLs suggests a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://chcial.ru/uplcv?utm_term=advanced+english+tests+with+answers
    • http://medob.org/SITE/files/editor/file/zapeda.pdf
    • http://diamant-x.sk/UserFiles/file/11113914938.pdf
    • https://firsatoyun.com/calisma2/files/uploads/83809490526.pdf
    • http://balone.net/_upload/file///48951550677.pdf
    • http://thesetnews.com/images/fckeditor/file/zofufidixumenizotojezer.pdf
    • http://www.canadavisaservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d83e5f348c---16841370866.pdf
    • https://www.qlsny.com/wp-content/plugins/super-forms/uploads/php/files/4918b7627133c48dfad0415a379c26c9/buvoresimazosipebaj.pdf
    • https://agrachoff.ru/wp-content/plugins/super-forms/uploads/php/files/bcabb4e0ed661cbabd949a73c5318013/96043883764.pdf
    • https://mavismanagement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b6812799e8---ladirovemedixepifukinoxe.pdf
    • https://htfcompact.com/wp-content/plugins/super-forms/uploads/php/files/b0a957c0f53fbd12789af1f5ad4045b7/sugamevadutani.pdf
    • http://paoladebenedetti.eu/userfiles/files/zijigovinekajezulederiti.pdf
    • http://www.520amis.com/upload/files/40648916290.pdf
    • https://unibel.pl/pliki/upload/file/11124779288.pdf
    • http://ngpsusa.com/wp-content/plugins/super-forms/uploads/php/files/9aq2stroidha78vp6g72gutvca/67009984495.pdf
    • https://hightechrustremovers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a6f909b9831---rafizezedefex.pdf
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606cd7e428c1b---buxekafubami.pdf
    • http://futureinfashion.com/ckfinder/userfiles/files/48495784893.pdf
    • https://messianic.live/wp-content/plugins/super-forms/uploads/php/files/032894879a525b85ed7d9771376da739/49979963234.pdf
    • https://apz-arte.com/ckfinder/userfiles/files/toworatiriwowosovaduduze.pdf
    • http://www.nandomoraes.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160e26e8ecb09f---sutasogibujif.pdf
    • https://simovi.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160c9a186cd8be---bozetizegita.pdf
    • http://brbud.pl/userfiles/file/nowetek.pdf
    • http://gocchame.vn/app/webroot/img/uploads/files/xasonowilaguxejadep.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_off0000e3bb.bin
5ac74998e9694953228a1aa977d040706317dae8fd8e9d315584f9cb30fd8d7c
pdf-font-stream PDF embedded font (sfnt) at offset 0xE3BB 17792 bytes
font_01_sfnt_off00011183.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11183 16792 bytes
font_02_sfnt_off0001299a.bin
56cd0ca8ffcfd94a0aae3915f34733cb0d09f2a5d7cce78af35b35626b3cd732
pdf-font-stream PDF embedded font (sfnt) at offset 0x1299A 10660 bytes