Malicious PDF — malware analysis report

Static analysis result for SHA-256 a16bc34a3d5fd73f…

MALICIOUS

PDF

92.9 KB Created: 2021-09-05 13:05:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5e1c342902a4ae0c020d065a2b478996 SHA-1: 6e94e4d968e5cd95aa4399c4530e68e89b38b630 SHA-256: a16bc34a3d5fd73fd0cd63511eca458d40493ce93bec00749680243fdc11ed95
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The embedded JavaScript is likely used to facilitate the redirection or exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9935

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://billsky.ee/files/file/mafisidel.pdf
    • https://diversifiedhumansolutions.com/wp-content/plugins/super-forms/uploads/php/files/ca7e1e0da349835823b9dcab5e3f8cab/ruviwokosori.pdf
    • http://hotstamping.pl/files/file/14394455140.pdf
    • https://www.harasportcenter.com/wp-content/plugins/super-forms/uploads/php/files/i8ec3odmrq5mpjh7ekaplo8fjo/64226951968.pdf
    • https://aimhc.com/userfiles/file/74329799937.pdf
    • http://audiomaster.se/wp-content/plugins/formcraft/file-upload/server/content/files/1607e7ca551932---24479087076.pdf
    • https://lensprovn.com/ckfinder/userfiles/files/3214643598.pdf
    • http://crystalnymph.by/wp-content/plugins/super-forms/uploads/php/files/c6e390b2ae9c295a8f899baf083d3b98/13119326898.pdf
    • https://promocionesnma.com/wp-content/plugins/super-forms/uploads/php/files/2ef4bbc98af160e81d4586020fd8e97f/panokomawinud.pdf
    • https://rajatotogroup2.com/contents/files/jukoxapa.pdf
    • http://festivaldeliteraturadepereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f94d3bc37a---61482529903.pdf
    • https://bellevuecommunityfoodbank.org/wp-content/plugins/super-forms/uploads/php/files/65527fe1babd7065454ce2a5be4de791/xuvuguxefezijeriv.pdf
    • http://smartmedicaleg.com/wp-content/plugins/formcraft/file-upload/server/content/files/161094bdd708ab---85507930917.pdf
    • http://skyrunarser.com/js/fckeditor/editor/filemanager/connectors/php/connector.php/upfiles/file/210719050729489753yg0szl.pdf
    • https://otdelkamos.ru/wp-content/plugins/super-forms/uploads/php/files/0a176037270f13e55ed8631666c8cc78/73850191067.pdf
    • https://paperland.bg/uploads/file/60709962168.pdf
    • http://uat.ideadunes.com/projects/ideadunes-portfolio-site/wp-content/plugins/formcraft/file-upload/server/content/files/16103cc5ee79ad---napitedukumibezopisuzesup.pdf
    • http://htygroup.com/upload/files/20611031675.pdf
    • https://ccaquebec.com/userupload/files/39619606861.pdf
    • http://anthonyvienna.com/sites/default/files/file/xejaretav.pdf
    • http://sepremprod.fr/www/images/mediamanager/2756645113.pdf
    • http://kraljicabih.com/wp-content/plugins/formcraft/file-upload/server/content/files/161006c79e4247---jowivozafojifutolisu.pdf
    • http://simsvizag.com/contentimages/file/mudibaxizivujisolaj.pdf
    • http://ccsctda.com/ckfinder/userfiles/files/20210904_212139.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=romanticism+criticism+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_off00010725.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10725 16792 bytes
font_01_sfnt_off00011f37.bin
4aaee0ca5fd8a37809463be0473f7ec0133e3d98f0031eca77caac72497f9b98
pdf-font-stream PDF embedded font (sfnt) at offset 0x11F37 18140 bytes
font_02_sfnt_off00014dc3.bin
f65b1aeb2042f41824627fd4a5982bcad43b4e8b8ed1f6dc4728bbdcaac0699b
pdf-font-stream PDF embedded font (sfnt) at offset 0x14DC3 10648 bytes