Malicious PDF — malware analysis report

Static analysis result for SHA-256 b511156810f7ff0f…

MALICIOUS

PDF

89.4 KB Created: 2021-09-18 06:23:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2ef6926552d514c1be67c76bb3ee640d SHA-1: a53310eb1cce6ef9a66868923a64d13a54181261 SHA-256: b511156810f7ff0fa4a607f23fcaa0d0a56d38ab551f26503ab493bc98e8a48b
164 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 JavaScript T1566.001 Spearphishing Attachment

The sample contains embedded JavaScript, a common technique for executing malicious code within PDFs. Additionally, it functions as a link farm, directing users to multiple external URLs, some of which are hosted on compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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.
  • 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://agataklimowska.pl/userfiles/file/kutarowijidubuwadepanefis.pdf
    • http://www.theagentpipeline.com/wp-content/plugins/formcraft/file-upload/server/content/files/161449dd504e07---8141449250.pdf
    • https://www.tessilgiada.it/wp-content/plugins/formcraft/file-upload/server/content/files/161353eea10fc7---detixan.pdf
    • https://hamzakocakoglu.com/userfiles/file/66069269068.pdf
    • http://linpus.com/app/webroot/userfiles/files/lurav.pdf
    • https://vmgeducationtrust.org/home/vmgedu/public_html/public/userfiles/file/tesepoxutiwabonaxoz.pdf
    • http://kiavysocina.cz/UserFiles/File/23045767228.pdf
    • http://bischofs-scheune.de/userfiles/file/fabugure.pdf
    • https://leavereview.com/customerinterview/ckfinder/userfiles/files/nutoponaperovifawag.pdf
    • https://komunalno.vrgorac.hr/files/xuwisinokomuduj.pdf
    • http://restaurant-lyons.fr/userfiles/file/zigewagigateri.pdf
    • http://technology-mp.it/userfiles/files/16346296586.pdf
    • http://sieuthimaynhapkhau.com/upload/files/43664563721.pdf
    • https://drosamahetta.com/userfiles/file/vefilivopo.pdf
    • https://prokoncept.hu/admin/blogfck/image/file/33227775443.pdf
    • https://lederstuhl-shop.de/ckfinder/userfiles/files/43338698963.pdf
    • http://gunjanjain.com/app/webroot/js/uploads/files/rirumazufugupogufafojuxi.pdf
    • http://ekvatorbl.com/userfiles/file/dixepitipowevix.pdf
    • https://bursaceviritercume.com/wp-content/plugins/formcraft/file-upload/server/content/files/161338f7a3c3ea---tawajup.pdf
    • http://nhasachthunam.com/upload/files/gilusovufunudeduworul.pdf
    • https://renfrewareahealthvillage.ca/ckfinder/userfiles/files/gedaxagipuxesimifikegito.pdf
    • https://freeunlock.com/uploads/file/16759692851.pdf
    • https://www.havanasalsa-dance-tours.com/wp-content/plugins/super-forms/uploads/php/files/bc1d0223d227196fbab25d60d864c0e9/54408039104.pdf
    • http://guoyangmoju.com/userfiles/files/21713629084.pdf
    • http://www.martiusstaden.org.br/js/ckfinder/userfiles/files/79425622369.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=app+to+transfer+photos+from+android+to+pc
    • 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_off0000f9e9.bin
fe5e4ad9144c4ab3df99c41cb4ff7e511f465d15515a2ef6cb78a9e9748e366f
pdf-font-stream PDF embedded font (sfnt) at offset 0xF9E9 17308 bytes
font_01_sfnt_off000126d2.bin
1fcb5b26445f7008199392d32505e93a8690993a6eabdac23a2c59e43a3499b5
pdf-font-stream PDF embedded font (sfnt) at offset 0x126D2 10820 bytes
font_02_sfnt_off00013f98.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13F98 16792 bytes