Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb43b11b1e8cfb87…

MALICIOUS

PDF

75.8 KB Created: 2021-09-29 13:38:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 46b31a5200d5a2c32cf7781934f5f194 SHA-1: 456a1962cddb204552acbb9a5027926fdff84e56 SHA-256: cb43b11b1e8cfb872a0457f85829347ce2df3169e33a17d5bef90098554f2cb6
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by a machine learning classifier and ClamAV, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, with numerous external URLs pointing to potentially compromised or disposable hosting. These links likely serve as lures for phishing attacks or to distribute further malware payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

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://sicompk.com/survey/userfiles/files/garerebomumafatosadis.pdf In PDF document text
    • http://maciejabramowicz.pl/upload/files/file/pimev.pdfIn PDF document text
    • http://skisun.it/userfiles/files/1919518894.pdfIn PDF document text
    • http://haisushitogo.com/uploads/files/pojiraw.pdfIn PDF document text
    • http://jsdarvin.com/files/94877388565.pdfIn PDF document text
    • https://kamhosting.nl/ckfinder/userfiles/files/95476249028.pdfIn PDF document text
    • https://landlorddebtadvisory.com/wp-content/plugins/super-forms/uploads/php/files/4b425e2333b71e60b97c45d2818a5617/33234542808.pdfIn PDF document text
    • http://salkim.com/userfiles/file/92260193154.pdfIn PDF document text
    • https://www.grandeprairie.org/wp-content/plugins/formcraft/file-upload/server/content/files/161529fe2da206---bazonetopilovanula.pdfIn PDF document text
    • https://trucraftsmanship.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e5560cba67---dofirikad.pdfIn PDF document text
    • https://mimpishio2bet.net/contents/files/8510689466.pdfIn PDF document text
    • http://wtmongolia.com/materials/file/40501554991.pdfIn PDF document text
    • http://www.alfapilates.pl/upload/file/65766781274.pdfIn PDF document text
    • http://holzbau-napetschnig.at/berirabifiji.pdfIn PDF document text
    • http://universalthailand.com/images/uploads/ckfinder/files/27972893885.pdfIn PDF document text
    • https://cbolean.com/wp-content/plugins/super-forms/uploads/php/files/803ca9b39e25586dcccf9a91db48a341/mopikimato.pdfIn PDF document text
    • https://www.getfitcrew.com/wp-content/plugins/formcraft/file-upload/server/content/files/16151dbcb5fffd---vuxiralezogaz.pdfIn PDF document text
    • http://rigassprotes.lv/uploadz/file/4297375249.pdfIn PDF document text
    • http://www.css-jp.com/upfile/files/2021/09/22/72702425970.pdfIn PDF document text
    • http://f-okinawa.com/img/tmp/files/luginakazerisowodope.pdfIn PDF document text
    • http://ebd.su/UFD/7623/files/detajotofelejidefugotak.pdfIn PDF document text
    • https://urbanshapes.in/userfiles/file/40714710675.pdfIn PDF document text
    • https://szaniterplaza.hu/ckfinder/userfiles/files/rakef.pdfIn PDF document text
    • http://isisthailand.org/file_media/file_image/file/rejilofasupinuwubikod.pdfIn PDF document text
    • https://metrosecuritynepal.com/assets/userfiles/files/13765768300.pdfIn PDF document text
    • https://777mto.com/contents/files/bidozupotetonogalowurupuv.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=actors+in+joe+dirtPDF 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_off0000c018.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC018 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d82a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD82A 19208 bytes
SHA-256: 8870f09db18e0776f6dbf3511771316c0a57301e4b3f835e6924f2956e3ebc8f
font_02_sfnt_off00010a65.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A65 10264 bytes
SHA-256: fcbdaee40fc6b8f5c0b801169851b5dd24736c649a3e2cf9ca57f20add232141