Malicious PDF — malware analysis report

Static analysis result for SHA-256 b2b79a20f18d4028…

MALICIOUS

PDF

82.0 KB Created: 2021-09-04 14:37:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: 5c2f45388d13e197feb655477b534310 SHA-1: 2ada26eff63bff87b608a4aa5b9c703cc59828dd SHA-256: b2b79a20f18d4028a020a08e9bf664a4507bfe15e44a774d4148ddbd7ddb4650
164 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://huntic.ru/uplcv?utm_term=pixl+maths+worksheets PDF link annotation
    • http://informerfitness.com/wp-content/plugins/super-forms/uploads/php/files/aa38f2268bb79c5b2f30b5a247b46515/10805696540.pdfIn PDF document text
    • http://adabaskimerkezi.com/upload/file/kumomivodasawedafiwola.pdfIn PDF document text
    • http://boilerservis.ru/uploads/files/26667587489.pdfIn PDF document text
    • http://antwerp-reefer-tournament.be/argt/files/7805953076.pdfIn PDF document text
    • https://syntellect.ru/Repository/file/muzawaforetikem.pdfIn PDF document text
    • http://www.altrus.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1607e42a675eb2---mutosifitipopinefoku.pdfIn PDF document text
    • http://levne-pohary.cz/UserFiles/File/xawawopuxozovavujigax.pdfIn PDF document text
    • https://tecsal.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c2f1b11a2cc---visobanokonixawa.pdfIn PDF document text
    • https://www.ogblfrontaliers.fr/wp-content/plugins/super-forms/uploads/php/files/g1ppd183men2qn7h5hu2rqb4uq/jifovu.pdfIn PDF document text
    • https://www.fangjin.org/ckfinder/userfiles/files/80966344594.pdfIn PDF document text
    • http://cedarvalekansas.com/clients/875954/File/vazetive.pdfIn PDF document text
    • http://mp-journal.com/media/file/mibeg.pdfIn PDF document text
    • https://iamluno.com/wp-content/plugins/formcraft/file-upload/server/content/files/160964b0a2a31e---98589972314.pdfIn PDF document text
    • http://chukgoobok.com/files/fckeditor/file/95319346390.pdfIn PDF document text
    • https://hkbca.org/UploadFiles/file/20210807233003169.pdfIn PDF document text
    • http://dharmapuridiocese.com/svnprojects/DHD/Source/images/files/58820601767.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/161048d21841ac---weweviserutafamijozax.pdfIn PDF document text
    • https://kop-trans.pl/uploads/userfiles/files/fagemovuxikawogox.pdfIn PDF document text
    • https://www.kcequipment.com.au/wp-content/plugins/super-forms/uploads/php/files/465c3618daa132e8a74119b81201cfc9/kaloru.pdfIn PDF document text
    • http://humanitool.ru/userfiles/file/verepupolalefulaxosopifel.pdfIn PDF document text
    • https://getadoc.in/ckfinder/userfiles/files/sufalidum.pdfIn PDF document text
    • https://aquaticlandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077c702b1fcf---32167094405.pdfIn PDF document text
    • https://journeypeople.cc/wp-content/plugins/super-forms/uploads/php/files/16ed5988c654d965ca85946101a5dd55/doperidijanamep.pdfIn PDF document text
    • http://cooleywestbrook.com/clients/865832/File/72407720777.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_off0000d959.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD959 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f170.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF170 10552 bytes
SHA-256: bf87eb7fcc70e9cd7e7a32390ddbba20765de7018372312cb36b9759865813eb
font_02_sfnt_off00010995.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10995 18944 bytes
SHA-256: a9f16a7c51042630d104e9b1818f650f0b390e2012ddc53da8c766cc5e072869