Malicious PDF — malware analysis report

Static analysis result for SHA-256 ae84e31a4123d4ac…

MALICIOUS

PDF

83.3 KB Created: 2021-06-30 02:00:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: aad5bba861f75407a0690f1ea9081bfc SHA-1: ac0a7ec6d79e371dc8b0c52cd655c14c21e205d0 SHA-256: ae84e31a4123d4acfb33ba42d22edb40c17aa868b3b89a76cec3230cf6e0208c
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, with numerous URLs pointing to compromised WordPress sites, likely serving as a distribution point for phishing or malware. The embedded URLs and the nature of the link farm suggest an attempt to lure users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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://becro-plast.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1606d90696e900---87624524298.pdf
    • https://duext.com/wp-content/plugins/super-forms/uploads/php/files/60ab3569f41a90eaf0fd9796ee19e0a7/50795335925.pdf
    • https://slavica.ru/wp-content/plugins/super-forms/uploads/php/files/5ac857fe63dd23a5c45684911ef34782/juroxuvepanikitimixo.pdf
    • http://milcontabil.com.br/wp-content/plugins/super-forms/uploads/php/files/34g0bjug15tovtm5od1tqilt56/94343988820.pdf
    • https://www.brunosistemi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160777b10b06c2---pezinozisuva.pdf
    • https://sportli.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/1606d99a01b263---78644674513.pdf
    • https://jetaime-shop.com/files/xudugoburogezilu.pdf
    • https://unitedcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608826184e547---80814968090.pdf
    • http://metabolit-plus.ru/files/file/gamosapupixaxefivib.pdf
    • https://www.advids.co/wp-content/plugins/formcraft/file-upload/server/content/files/1609dd48907fa0---87521597428.pdf
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/160db96e45b123---wazesivijegozejosewapo.pdf
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/16078ac8c23eb5---61591238969.pdf
    • https://familienarbeit3plus.ch/userfiles/files/50909467084.pdf
    • http://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609144fc38d89---lojujilanoxivuvafuzokile.pdf
    • https://diversifiedhumansolutions.com/wp-content/plugins/super-forms/uploads/php/files/13616470542a48445673d7ca5c39a2b3/dozor.pdf
    • http://e-hematologica.pl/users//file/26794764363.pdf
    • https://rfcorporation.net/wp-content/plugins/super-forms/uploads/php/files/53ed803c289ae6402bf8658299076a66/zigojesenusemareb.pdf
    • http://alarcon-v.com/editor_upload_image/file/zaloregoponogepadumomozuk.pdf
    • https://davaocarrental.com/images/file/89486073493.pdf
    • https://realwebguys.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c7554656c5---90207276030.pdf
    • http://nwatchonline.net/userfiles/file/notevigosevotak.pdf
    • http://elsekmont.eu/userfiles/file/92657452395.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=questions+and+answers+on+c+programming
    • 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_off0000e182.bin
c9e71ec5be09dee47238a82f9505b39794645f190e2814e615c57ea7f1d4de3b
pdf-font-stream PDF embedded font (sfnt) at offset 0xE182 17104 bytes
font_01_sfnt_off00010e1b.bin
d6c88896d75941190b9d155235e1bce79aa29c08a8cb33b84412b62d0ea0f813
pdf-font-stream PDF embedded font (sfnt) at offset 0x10E1B 11056 bytes
font_02_sfnt_off000127d4.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x127D4 16792 bytes