Malicious PDF — malware analysis report

Static analysis result for SHA-256 37ea2736adbb7cb0…

MALICIOUS

PDF

79.1 KB Created: 2021-09-04 22:34:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: e8f422037a6cf116cd2cddc7e413bc57 SHA-1: 96b46f047881a488add4b7c7b5f3c9962e636f0d SHA-256: 37ea2736adbb7cb0e89bcedefa4948d6aae2102ab8718f6625200f7e3a57402a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, indicating a phishing or trojan-like behavior. It contains a link farm with numerous URLs, many hosted on compromised WordPress sites, suggesting an attempt to distribute malicious content or manipulate search engine results. No scripts were extracted, but the presence of multiple external URIs points to a phishing or content distribution attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

Heuristics 6

  • 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.
  • 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 https://wastran.ru/uplcv?utm_term=xml+to+pdf+online+convert PDF link annotation
    • https://www.ciabrini-immobilier.com/wp-content/plugins/super-forms/uploads/php/files/nmq7hvfss9u2ims78mnl4l9fak/lukofepatuki.pdfIn PDF document text
    • http://www.taxivanclass.com/uploads/ckfinder/files/94411102787.pdfIn PDF document text
    • http://cavusofis.com/images_upload/files/vinufizawop.pdfIn PDF document text
    • https://sayurhijau.com/contents//files/25115535681.pdfIn PDF document text
    • http://botosani.ro/img/uploads/file/kowopegu.pdfIn PDF document text
    • http://maplewoodmachine.com/clients/1/17/17f0ea2532424b9b8bf99baf53cd3763/File/83482911980.pdfIn PDF document text
    • https://yucekalipmakina.com/tsrm1/img/userfiles/file/gojowetimifajunokuzo.pdfIn PDF document text
    • https://dangeloremodeling.com/nbloom/fckuploads/file/95782775025.pdfIn PDF document text
    • http://grandhotelbulgaria.com/userfiles/file/tibojomadoxegimasurak.pdfIn PDF document text
    • https://ms02bet.com/contents//files/39919981593.pdfIn PDF document text
    • https://controlcert.se/wp-content/plugins/formcraft/file-upload/server/content/files/160d5490fce114---doleb.pdfIn PDF document text
    • https://regionalhealthprogramsww.com/images/file/48140174995.pdfIn PDF document text
    • http://milwaukee.center/userfiles/file/ritewomokuboram.pdfIn PDF document text
    • https://a2designbg.com/userfiles/file/revunefosolo.pdfIn PDF document text
    • http://7166867.ru/ckfinder/userfiles/files/toxalawanok.pdfIn PDF document text
    • http://fairmonteast1975.com/clients/0/01/014dde3c838f86fef2ac1d31a86c415b/File/velasibadizujofazif.pdfIn PDF document text
    • https://qualitycountscleaning.com/wp-content/plugins/super-forms/uploads/php/files/e1410c1c8f5c2a7aa5a2b7999bd79d42/27312075268.pdfIn PDF document text
    • https://trimix.bg/UserFiles/File/83177406843.pdfIn PDF document text
    • http://psycare-spb.com/userfiles/file/4345659369.pdfIn PDF document text
    • http://mlsconsulting.net/cms/files/File/8587369447.pdfIn PDF document text
    • http://sylvianapoles.com/clients/e/e6/e63d90d46a840f0b3195f531cec11f6e/File/23449561975.pdfIn PDF document text
    • https://bxthirteen.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/76a7951dc2e5e0f2fbfeec3a8f097045/newitopoxabivan.pdfIn PDF document text
    • 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_off0000cfea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFEA 10524 bytes
SHA-256: c26b3b0f7a5dd7abff8896d78eeaf6d6b0df9dbf7c961c1e7a00bfc9fe467fb9
font_01_sfnt_off0000e7c7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7C7 18616 bytes
SHA-256: 98e3e4379811d5022816f8cfe7099d3ff0c99b6c1e1982ef0ad5baa0630a2ff5
font_02_sfnt_off00011731.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11731 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1