Malicious PDF — malware analysis report

Static analysis result for SHA-256 3791248c0c710425…

MALICIOUS

PDF

84.7 KB Created: 2021-09-16 13:54:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: e5db9896b63be2f74e213a910e48a1c2 SHA-1: 7ad43966932ba088a1ee07eba9b28e0dc651d1b0 SHA-256: 3791248c0c7104254e84b5b9384064aaca565431fcd6f932a7e82310e22da39b
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs that point to compromised WordPress sites and disposable domains, suggesting a link farm or phishing campaign. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to exploiting PDF vulnerabilities or delivering malicious content via these links. No scripts were extracted, limiting the analysis of direct execution vectors.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://laborke.ru/uplcv?utm_term=avro+bangla+keyboard+for+android+phone PDF link annotation
    • http://triumphtoday.org/wp-content/plugins/formcraft/file-upload/server/content/files/1614215619c23a---71724389124.pdfIn PDF document text
    • http://www.wallisandemmanuel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613057a57b866---57163093015.pdfIn PDF document text
    • http://newtrichur.com/userfiles/file/dosubowopoboku.pdfIn PDF document text
    • https://www.beadvised.co.uk/wp-content/plugins/super-forms/uploads/php/files/7b0fe1657e2fa14fba9fed202fb51de0/xazuxovikipumoxokofimakuw.pdfIn PDF document text
    • http://aiaato.com/FileData/ckfinder/files/20210915_855E347EAD76567B.pdfIn PDF document text
    • http://01host.ru/userfiles/files/buluduvolesobosutavijus.pdfIn PDF document text
    • https://quangtriasianwindow.com/uploads/image/files/tanivunamaderezeminomafu.pdfIn PDF document text
    • http://ganteltechnology.com/system/userfiles/file/xipisipuxirukem.pdfIn PDF document text
    • http://mayingiabao.com/upload/files/19140925622.pdfIn PDF document text
    • https://www.reliancecareuk.com/wp-content/plugins/super-forms/uploads/php/files/c04782c54873877d1626cece5588f4a8/39798651141.pdfIn PDF document text
    • http://cnc-soustruzeni.cz/files/file/41159596666.pdfIn PDF document text
    • http://fiumaradelsossio.it/userfiles/files/3523769221.pdfIn PDF document text
    • http://mprime.net/ckfinder/userfiles/files/pimutereduv.pdfIn PDF document text
    • https://www.supremecaravans.com.au/application/third_party/ckfinder/userfiles/files/paxazadejavuriwadim.pdfIn PDF document text
    • http://agriturismolescuderie.eu/userfiles/files/wusotalepamoxapajir.pdfIn PDF document text
    • http://kamnitikamini.si/upload/files/75133024545.pdfIn PDF document text
    • https://hophamthaibinh.com/upload/files/givamor.pdfIn PDF document text
    • https://hsegroup.ru/wp-content/plugins/super-forms/uploads/php/files/ekcpua1n0trr3h65lcu3k52rq7/92656176426.pdfIn PDF document text
    • http://baohanhranghm.com/upload/img/files/4610781559.pdfIn PDF document text
    • https://big-affaires.com/img/pics/files/mivamifaj.pdfIn PDF document text
    • http://ip-golubev.ru/ckfinder/userfiles/files/tutezukiwuzoduwibunobowo.pdfIn PDF document text
    • http://aquarium-kochi.com/app/webroot/ckfinder/userfiles/files/43870912836.pdfIn PDF document text
    • https://ilexgold.com/app/webroot/files/userfiles/files/92972022271.pdfIn PDF document text
    • http://rs-entp.com/upload/file/18776664683.pdfIn PDF document text
    • https://chennothinterios.com/uploads/file/901931562.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_off0000e679.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE679 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fe90.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE90 10904 bytes
SHA-256: 2d779ccde65b1c5936d56979cffcf547641499957f67cc7480ab110c6f464b35
font_02_sfnt_off00011749.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11749 17540 bytes
SHA-256: 5ef32899b0b620ba05d976567c83c036699802b63c0f9a9082edf83ab254f419