Malicious PDF — malware analysis report

Static analysis result for SHA-256 b309f2ba06fd4a85…

MALICIOUS

PDF

69.9 KB Created: 2021-09-18 04:53:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: ea3283a1f41c94aec55f6ac7ee7399e6 SHA-1: 109ce88b8a66a84df78b1355b938ec72b2572b2a SHA-256: b309f2ba06fd4a855d9d174f478a81f14cd9c8185c7785bf3664a52080e79219
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. It contains numerous links, many pointing to compromised CMS upload storage or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of external URIs and the overall structure indicate an attempt to lure victims to external sites, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://audiohrestomatiya.ru/content/file/jafifop.pdf In PDF document text
    • http://candientushinko.com/images/file/16455344885.pdfIn PDF document text
    • http://www.magicapro.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613905ac993a7---remomivepur.pdfIn PDF document text
    • http://topbondtape.com/uploadss/file/lexobatijokumabe.pdfIn PDF document text
    • http://camara.acessoainformacao.org/uploads/ckfinder/files/57800982111.pdfIn PDF document text
    • http://peetersinstallatietechniek.nl/upload/files/410042841.pdfIn PDF document text
    • http://villaturri.it/wp-content/plugins/formcraft/file-upload/server/content/files/161324e73c9004---kajexadiv.pdfIn PDF document text
    • http://aptwash.com/userData/ebizro_board/file/givaxoruzilut.pdfIn PDF document text
    • http://flomojapan.com/upload/files/xexidinezaderabanig.pdfIn PDF document text
    • https://srmhomes.com/images/bulk_images/files/40285506006.pdfIn PDF document text
    • http://epmresearch.org/userfiles/files/zenomuwesexurinumajute.pdfIn PDF document text
    • http://fujieshubao.com/zk/UploadFile/file/2021091807450973499.pdfIn PDF document text
    • http://uspeh-kursk.ru/ckfinder/userfiles/files/77818867239.pdfIn PDF document text
    • http://kdbelektrotechniek.nl/uploads/file/jagojiridekosusobesupi.pdfIn PDF document text
    • http://baanpowertrain.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136a41c68413---87436782113.pdfIn PDF document text
    • https://kit-veron.my/ckfinder/userfiles/files/mufugifi.pdfIn PDF document text
    • https://takipcisec.com/calisma2/files/uploads/60087242092.pdfIn PDF document text
    • http://www.brickchamber.com/ckfinder/userfiles/files/28127371389.pdfIn PDF document text
    • http://yasaitogo.com/uploads/files/42135402016.pdfIn PDF document text
    • http://www.auditsi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16142965df1be8---9522971759.pdfIn PDF document text
    • http://ivankotov.ru/img/lib/file/xaxevekunotiduwisulosabe.pdfIn PDF document text
    • http://citygclub.com/ckupload/files/mowamubowujopuzexosababo.pdfIn PDF document text
    • https://mjrspot.com/fckimages/file/72939550763.pdfIn PDF document text
    • http://synagoge-stommeln.de/ckfinder/userfiles/files/dezewexamavone.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=cheap+phones+in+nigeria+2020PDF link annotation
    • 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_off0000b3ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB3AB 10660 bytes
SHA-256: 3c645190dcc75650c344735d9cd7404e15a7eee02b44748391419ffb52fe4864
font_01_sfnt_off0000cc15.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC15 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e427.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE427 15032 bytes
SHA-256: ef4633245b5e4068285361a00d73bc812a1b59c83433ff1838097a017562a3c5