Malicious PDF — malware analysis report

Static analysis result for SHA-256 f510c2b8d995f269…

MALICIOUS

PDF

71.7 KB Created: 2021-09-19 08:18:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: b61a8697f58b10c686db6f60a053a3d3 SHA-1: 63347946bae2115c0adaedbd521d1cb080d285ad SHA-256: f510c2b8d995f269b166ab99de14781376599f9b614590cd76a1b9e242ed5fff
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, with multiple heuristics indicating it functions as a link farm. The embedded URLs and document structure suggest an attempt to redirect users to potentially malicious or phishing sites, leveraging compromised CMS uploads and disposable hosting. No scripts were extracted, but the overall pattern points to a phishing or SEO-based malicious campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 https://oniceh.ru/uplcv?utm_term=best+music+application+for+android PDF link annotation
    • https://osakadentalcare.com/contents/files/52573876384.pdfIn PDF document text
    • http://proximeo.com/ckfinder/userfiles/files/77899967457.pdfIn PDF document text
    • http://lanaecoloridabruzzo.it/userfiles/file/2929467284.pdfIn PDF document text
    • http://explosivedevices.ru/media/file/tugemasonukusu.pdfIn PDF document text
    • https://brazilairporttransfers.com/ckfinder/userfiles/files/lebozobomat.pdfIn PDF document text
    • http://kompassztuki.pl/Image/files/kasemovudofipen.pdfIn PDF document text
    • http://rosabaum.de/web/editor/files/59783278118.pdfIn PDF document text
    • https://hunglivet.com/uploads/files/202109010711208249.pdfIn PDF document text
    • http://wonderpanel.com/app/webroot/img/file/lodatobagesomeduje.pdfIn PDF document text
    • https://ivfnna.gr/wp-content/plugins/super-forms/uploads/php/files/2001708c22357785bff33bdd8fba9b70/5700893224.pdfIn PDF document text
    • https://footballsod.com/images/ck-uploads/files/votagoropurotiteriz.pdfIn PDF document text
    • http://beiwendq.com/data/attachment/file/86947332456.pdfIn PDF document text
    • http://hcstonetw.com/uploads/files/202109090945457647.pdfIn PDF document text
    • http://habitat3.eu/userfiles/files/fomifisapalolu.pdfIn PDF document text
    • https://victory-agency.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138b871efad8---22845690791.pdfIn PDF document text
    • https://phucatgarment.com.vn/ckfinder/userfiles/files/sufabagajunokobani.pdfIn PDF document text
    • http://covina.crazyrockinsushi.com/uploads/files/88869716636.pdfIn PDF document text
    • http://mp-journal.com/media/file/xukut.pdfIn PDF document text
    • https://naseeha.org/wp-content/plugins/super-forms/uploads/php/files/2f617cc301766f4c5c37367791077ab1/57000862432.pdfIn PDF document text
    • https://middletonchambers.com/ckfinder/userfiles/files/28285995295.pdfIn PDF document text
    • https://alatheir.com/atheirwsfiles/file/37355799089.pdfIn PDF document text
    • http://gocchame.vn/app/webroot/img/uploads/files/zapufabidepen.pdfIn PDF document text
    • http://sluchatka-shop.cz/files/upload/files/wetalo.pdfIn PDF document text
    • http://www.egavilanes.com/ckfinder/userfiles/files/81175518359.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_off0000b8f2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB8F2 10936 bytes
SHA-256: 887ac0f6cca57a1389eee2ce9ea365b68e23e3c2e019b9cc926f924f8f32f690
font_01_sfnt_off0000d244.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD244 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ea56.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA56 15144 bytes
SHA-256: fb602ce385747a8d71d5186b8a64c696ac0ac36074b904c9caa4a2820c0fffb0