Malicious PDF — malware analysis report

Static analysis result for SHA-256 1f87dc134308ba32…

MALICIOUS

PDF

82.4 KB Created: 2021-09-17 01:49:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: dc7f233038793dc28c3b762abe745730 SHA-1: 168dcaced1122ca2d66eec11857a7fea4714e3f5 SHA-256: 1f87dc134308ba32ac040aae044dc55cf387ea89ff3d0ef343cfd149b1bcc7f3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file is identified as malicious by ClamAV and an ML classifier, and exhibits characteristics of a link farm. Multiple heuristics indicate the PDF contains links pointing to compromised WordPress uploads and other disposable hosting, suggesting an attempt to redirect users to malicious sites. The ML classifier's high confidence score further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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 http://vvk-wiedermann.at/userfiles/file/dabelufetip.pdf In PDF document text
    • http://danangsculpture.com/uploads/image/files/sebigawupekivedarelu.pdfIn PDF document text
    • http://xindeshiye.com/uploadfile/file///2021090807084371.pdfIn PDF document text
    • https://www.frontierexim.com/wp-content/plugins/super-forms/uploads/php/files/709irkpv2qh9m0u64spfc0jpf6/ranelutuzag.pdfIn PDF document text
    • http://drukarnia-warszawa.pl/pliki/file/97652570557.pdfIn PDF document text
    • http://stigstudiotecnico.it/userfiles/files/52081351158.pdfIn PDF document text
    • https://doosradashak.in/ci/userfiles/files/39037160845.pdfIn PDF document text
    • http://vegman-kzn.com/ckfinder/userfiles/files/winexigemudatasiginije.pdfIn PDF document text
    • https://path.mn/userfiles/files/61905451890.pdfIn PDF document text
    • http://tubemakingmachine.com/uploadfile/files/kafukulokejamawe.pdfIn PDF document text
    • https://sluganarodu.org/userfiles/files/kiduxagaxu.pdfIn PDF document text
    • http://english-island.pl/wp-content/plugins/super-forms/uploads/php/files/mke43uiphv68c69p917t1j00e4/wekezuviri.pdfIn PDF document text
    • http://diysmart.net/userfiles/file/pumexagitisawigumasaw.pdfIn PDF document text
    • https://enkaotomatikkapi.com/depo/sayfaresim/file/24515887945.pdfIn PDF document text
    • http://svaz-podnikani.cz/files/file/norob.pdfIn PDF document text
    • https://mokhalasati.com/userfiles/files/folozipewizegib.pdfIn PDF document text
    • http://tentimesneedlehill.com/UPFILE/userfiles/files/80227422288.pdfIn PDF document text
    • http://ulv-fogger.es/d/files/finagizowijumir.pdfIn PDF document text
    • https://dafelia.com/files/romodopavume.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/161433613d19ab---39566261352.pdfIn PDF document text
    • https://www.c2commercial.com/wp-content/plugins/super-forms/uploads/php/files/f494e5db5b250921c38172c892ea6305/gubufakinifidirixa.pdfIn PDF document text
    • http://www.rebranded.tv/wp-content/plugins/formcraft/file-upload/server/content/files/16140ae13193df---fexegux.pdfIn PDF document text
    • https://agribusiness.pk/wp-content/plugins/formcraft/file-upload/server/content/files/16138734a9844e---degugupepojajosulo.pdfIn PDF document text
    • https://dottoridegregorio.it/public/file/76773975156.pdfIn PDF document text
    • http://aquitaine.annuaire-regional.com/ckfinder/userfiles/files/25260600114.pdfIn PDF document text
    • http://jjmcp.jp/userfiles/Image/file/74413993164.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=eclipse+android+tutorialPDF 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_off0000dbd9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBD9 18500 bytes
SHA-256: 909d41a8dff12dd090a7ffc9943021f7896b42e37954306b8d0ad300b124d01b
font_01_sfnt_off00010b51.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B51 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012368.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12368 10592 bytes
SHA-256: 8aa464d9a9d445fcb38f891fcecd11e669f28bc4c7934a4ffc0cf1f2da48382f