Malicious PDF — malware analysis report

Static analysis result for SHA-256 99142c5d65868f02…

MALICIOUS

PDF

96.2 KB Created: 2021-08-17 00:58:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: 688cb9ad83997c8345f18739f295441f SHA-1: 0f75a9d6015220684c1d2043c2499ea90faad952 SHA-256: 99142c5d65868f0254a742d4365141670c1a3aac1144a659227941e89a2fb56d
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and multiple external URIs, many of which point to compromised WordPress sites acting as link farms. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of JavaScript suggests an attempt to execute malicious code within the PDF viewer.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9888

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://www.stratcareerservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083721ee5c5d---90971315228.pdf In PDF document text
    • http://bogaarchitetti.it/userfiles/files/tigifumus.pdfIn PDF document text
    • https://completecollegestrategies.com/wp-content/plugins/super-forms/uploads/php/files/95133b22a84bfcbe7c42172dec03d001/38307464659.pdfIn PDF document text
    • http://nontaromclinic.com/ckfinder/userfiles/files/2406629804.pdfIn PDF document text
    • https://linhngapt.vn/upload/files/jozeponaveni.pdfIn PDF document text
    • http://smartcookieacademy.com/wp-content/plugins/formcraft/file-upload/server/content/files/16114e23e05a6d---koguguvowefuparetomogos.pdfIn PDF document text
    • http://tubietelbar.hu/uploadfile/kojol.pdfIn PDF document text
    • http://thamdinhgiadaiquang.com/img/files/xirexuvebipo.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/70db48caf036de8834b985cee370079c/40877299678.pdfIn PDF document text
    • http://sjzhtchem.com/upload/files/41040097474.pdfIn PDF document text
    • http://lueckerreunion2020.com/clients/e/eb/eba09433058400eda594a485f9004317/File/49587686034.pdfIn PDF document text
    • http://mmprogetti.it/userfiles/files/96730982167.pdfIn PDF document text
    • https://www.pension-chevaux-haras-gabereau.fr/ckfinder/userfiles/files/18190178628.pdfIn PDF document text
    • http://conservationenergy.com/wp-content/plugins/formcraft/file-upload/server/content/files/16095d3dcd9ddf---84495096669.pdfIn PDF document text
    • http://madmojo.com/fckupload/file/livoginalojuxudi.pdfIn PDF document text
    • https://altonika.pro/files/fck/file/45998468721.pdfIn PDF document text
    • http://avtoarka.ru/wp-content/plugins/super-forms/uploads/php/files/9257f10ff13ce946d401cc102f49044b/52266432716.pdfIn PDF document text
    • https://siyata.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160988be66727a---bogurikonogo.pdfIn PDF document text
    • http://kondicionery-dolgoprudny.ru/upload_picture/file/bipofowat.pdfIn PDF document text
    • http://supair-lux.hu/ckfinder/userfiles/files/11813903844.pdfIn PDF document text
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ef74ad6f17---lotuzafovugepufojekuxiwet.pdfIn PDF document text
    • http://webdulich.com/js/ckfinder/userfiles/files/47717927735.pdfIn PDF document text
    • http://www.carolglassman.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b558e894892---xagegiru.pdfIn PDF document text
    • http://xn--l3cbpp3gh4a5g5c.com/userfiles/files/mawotakebogixodef.pdfIn PDF document text
    • http://www.mondzorgvesa-voorschoten.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160f259be5c37e---rovenosazulo.pdfIn PDF document text
    • http://fizjoactiv.eu/Upload/file/16854420776.pdfIn PDF document text
    • https://himarco.ir/basefile/himarcoir/files/97795386349.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=mapa+cognitivo+de+categor%C3%ADas+triangularPDF 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_off00010e24.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E24 18804 bytes
SHA-256: 1b4d289f0e7ec634db4b07f7d5d55b1250203dc3df8cbf46cedd96a788cae516
font_01_sfnt_off00013df0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13DF0 10908 bytes
SHA-256: 7e628ac1cda274d440867e9658a4acdf4fcedbb5772ba5250d7f87c65fa004ee
font_02_sfnt_off00015720.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15720 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1