Malicious PDF — malware analysis report

Static analysis result for SHA-256 709f7b377134b0ff…

MALICIOUS

PDF

69.9 KB Created: 2021-09-28 09:58:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 7db474c77381032a0c6be040fcd54e53 SHA-1: 29cf22635ffb13e070e2f038911d8eb8f7bbaf59 SHA-256: 709f7b377134b0ff4894406b81ef96b9747281ebc2235100efe0b5dd4c230b12
156 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs that point to various domains, many of which appear to be compromised or disposable hosting. Heuristics indicate this is a link farm designed to direct users to external sites, consistent with phishing or malware distribution tactics. The ML classifier and ClamAV detection strongly suggest malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 https://synerhu.ru/uplcv?utm_term=duo+mobile+for+android+7 PDF link annotation
    • http://jutaek.humenia.com/upload/userfiles/2021/09/files/210905064250.pdfIn PDF document text
    • http://www.trimbleexpress.sk/wp-content/plugins/formcraft/file-upload/server/content/files/1614085257c049---26887799986.pdfIn PDF document text
    • https://femagnet.com/upload/edu/article/file/17769124529.pdfIn PDF document text
    • http://fcraregistration.com/UploadedData/file/45922574710.pdfIn PDF document text
    • http://cnkls.com/userfiles/file/1632363460.pdfIn PDF document text
    • http://poetische-malerei.de/web/editor/files/7372931224.pdfIn PDF document text
    • http://msnladyboy.com/ckfinder/userfiles/files/9697647591.pdfIn PDF document text
    • http://www.playerclub.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16140be0572307---90509592820.pdfIn PDF document text
    • http://mizuho-co.net/file/ck/files/49777000558.pdfIn PDF document text
    • http://ros-audit.com/i/up/file/ledojopatalo.pdfIn PDF document text
    • https://www.frontieregypt.com/sites/all/libraries/ckfinder/userfiles/files/66717131397.pdfIn PDF document text
    • http://newo.ru/files/files/64562102701.pdfIn PDF document text
    • http://www.chatanakonci.cz/userfiles/file/42366066142.pdfIn PDF document text
    • http://ehomeforeclosure.org/images/file/64093343400.pdfIn PDF document text
    • http://ssp.by/var/upload/linojagibagufutomiren.pdfIn PDF document text
    • http://liveranigioielli.it/userfiles/files/71224643901.pdfIn PDF document text
    • http://lblussana.it/images/file/bawinobelafijidoru.pdfIn PDF document text
    • http://penzionnakrizankach.cz/ckfinder/userfiles/files/sejivumiv.pdfIn PDF document text
    • http://terralis.net/catalogue_dynamique/file/58440320783.pdfIn PDF document text
    • https://bestmiamiturf.com/wp-content/plugins/super-forms/uploads/php/files/ede90ad9a11bf86f2983d319c7f1688f/retitugisolov.pdfIn PDF document text
    • http://ambvetesopo.eu/userfiles/files/37264700929.pdfIn PDF document text
    • http://bibliotekaszamocin.pl/img/upload/files/liraf.pdfIn PDF document text
    • https://tavio.ru/files/file/98020771712.pdfIn PDF document text
    • https://mytekas.com/UserFiles/file/31213096349.pdfIn PDF document text
    • http://elezioni2014.gds.it/userfiles/file/90422677959.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_off0000b31a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB31A 10540 bytes
SHA-256: 7572455999ae8680cd4cdf30e2a4e9637eff1e806a5a54a55dd6292031586be3
font_01_sfnt_off0000cb0b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB0B 15344 bytes
SHA-256: a0dbed5f94e973ddbad103e46b1fe87bec8c00fb5a3155c849ea21489cbc9f4f
font_02_sfnt_off0000f1ac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1AC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1