Malicious PDF — malware analysis report

Static analysis result for SHA-256 797f852f8105ffb9…

MALICIOUS

PDF

94.7 KB Created: 2021-07-30 01:56:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-17
MD5: bccb853993b79def9be3f2227184ba25 SHA-1: 909d5982a4b2fac7f61e12c8ded34581021a654a SHA-256: 797f852f8105ffb98cb29038fbf32c12f64738bd0e85c0613cba8bdd8851be93
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to compromised websites hosting other PDF files. This suggests a phishing or malware distribution campaign, where the initial PDF serves as a lure to redirect users to malicious content.

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 http://519pf.com/userfiles/files/12488758437.pdf In PDF document text
    • https://rfcorporation.net/wp-content/plugins/super-forms/uploads/php/files/4e42d8c02cf6167f196c32b7c810c7cd/rukutufajamukulatajazu.pdfIn PDF document text
    • https://www.entornopublicitario.com/wp-content/plugins/super-forms/uploads/php/files/0aaec5a76cedf7cb81cba4dbe8346f6f/53184413112.pdfIn PDF document text
    • http://nct-vn.com/userfiles/file/bosomubaxemidabafapoxex.pdfIn PDF document text
    • http://dmn.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16098ad6408662---26366038738.pdfIn PDF document text
    • https://ancoraeducacion.com/images/81223007573.pdfIn PDF document text
    • http://medica-brno.com/files/46505171951.pdfIn PDF document text
    • https://limpjet.com.br/wp-content/plugins/super-forms/uploads/php/files/52f75b730f885ba2b0d52d2b1a577107/51221279937.pdfIn PDF document text
    • http://arci-mp.fr/admin/File/nexikirofixuvew.pdfIn PDF document text
    • http://friluftsgruppen.se/wp-content/plugins/formcraft/file-upload/server/content/files/1607117525fc35---68702657027.pdfIn PDF document text
    • http://ufnk.fr/app/webroot/files/file/wenotuvidasoz.pdfIn PDF document text
    • http://kartywspomnien.pl/uploads/assets/file/dupila.pdfIn PDF document text
    • https://choiceenergynetwork.com/wp-content/plugins/super-forms/uploads/php/files/f0e6defe1848c912af4f8fb7ce4fa894/1432042853.pdfIn PDF document text
    • http://www.thediethub.in/wp-content/plugins/formcraft/file-upload/server/content/files/160c685fdd6553---67719920241.pdfIn PDF document text
    • http://sotel-perm.ru/site/file/kemexuzun.pdfIn PDF document text
    • http://palaciodelosnavas.com/userfiles/file/99999256938.pdfIn PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/c70b1a7a4a254817fcd8860260e900a0/44447037725.pdfIn PDF document text
    • https://phase1acoustics.com/wp-content/plugins/formcraft/file-upload/server/content/files/160847c4518f73---60156575862.pdfIn PDF document text
    • http://www.uppld.org/wp-content/plugins/formcraft/file-upload/server/content/files/160c38b475dabe---nifazikijapitowitagifoxa.pdfIn PDF document text
    • https://alphaveneers.co.uk/wp-content/plugins/super-forms/uploads/php/files/1b6802a675842e065522d22b18edd49b/bibuwunexifebadadonu.pdfIn PDF document text
    • http://www.radiopopiatej.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab0a192abf1---fazuwuwot.pdfIn PDF document text
    • http://jhdjt.com/images/upload/File/vipokone.pdfIn PDF document text
    • https://albawadiroad.com/userfiles/files/makanokuguwubupa.pdfIn PDF document text
    • http://ljhalls.com/wp-content/plugins/super-forms/uploads/php/files/66a4427aebc7b3e60b39570cacf4ebf7/1134598777.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=la+crosse+technology+radio+controlled+analog+clock+instructionsPDF 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_off00010eeb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10EEB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000126fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x126FD 16748 bytes
SHA-256: 1c44c34b2043343578bcbd1e7d75065a199ef5e44289404b8e9da7b3c7dc27bc
font_02_sfnt_off00015258.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15258 10912 bytes
SHA-256: c23febf49d08fd2054a291386fdc16a3d5339fa8185a659740bca0155f2d7904