Malicious PDF — malware analysis report

Static analysis result for SHA-256 82a0f4e5fb8492d6…

MALICIOUS

PDF

81.5 KB Created: 2021-09-04 00:44:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 9030039780a826d150cbb4f80c606624 SHA-1: 115fc24cf8099ff6ebaac67b08cf5374229aec29 SHA-256: 82a0f4e5fb8492d6d3475a3af22d9b486496f6f05e2a53518361f39d7530cc25
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, pointing to numerous URLs hosted on compromised or disposable domains, likely to obscure the final destination and evade detection. While no scripts were explicitly extracted, the PDF structure and link farm behavior suggest it is designed to lure users to external sites, potentially for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://www.xn----9sbkvfu2aex3d.xn--p1ai/ckfinder/userfiles/files/27441107910.pdf In PDF document text
    • https://www.avenueroadadvertising.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c2c88696e6c---jamijotitopujovemegezivir.pdfIn PDF document text
    • https://honghow.com/ckfinder/userfiles/files/folofiguludedelafinibez.pdfIn PDF document text
    • http://kondicionery-krasnogorsk.ru/upload_picture/file/34148386344.pdfIn PDF document text
    • https://forumhotel.by/wp-content/plugins/super-forms/uploads/php/files/v9poruciru1fe7rafdqv0uok62/kesimigod.pdfIn PDF document text
    • https://dfa-finanz.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607d04bc19d7e---34738673851.pdfIn PDF document text
    • http://maidnheaven.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606fb8f931196---93182119048.pdfIn PDF document text
    • http://www.neocota.com/fckimages/file/77592703228.pdfIn PDF document text
    • https://popcouncilinstitute.org/wp-content/plugins/super-forms/uploads/php/files/cea2e979d218893565dc2b0297069aea/6619885968.pdfIn PDF document text
    • https://sweetestspaparty.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f218e85444---zesapafafafo.pdfIn PDF document text
    • https://sportuna.be/ckfinder/userfiles/files/47645155747.pdfIn PDF document text
    • http://leap-egypt.com/wp-content/plugins/formcraft/file-upload/server/content/files/160985a58a6a24---55751366000.pdfIn PDF document text
    • https://www.tangelo.no/wp-content/plugins/formcraft/file-upload/server/content/files/16087fb9668877---63366412758.pdfIn PDF document text
    • http://minhledtran.com/luutru/files/96668830093.pdfIn PDF document text
    • http://olech-rzeszow.pl/userfiles/file/nojabevivapapezu.pdfIn PDF document text
    • https://oneremote.ru/wp-content/plugins/super-forms/uploads/php/files/0b2d9f00ae5a1a060a0132feecc07882/rokugepilom.pdfIn PDF document text
    • http://www.macrolepidoptera.hu/userfiles/files/mitaxixepamufevubijuzokuk.pdfIn PDF document text
    • http://fontanarosaserigrafia.it/userfiles/file/18764567694.pdfIn PDF document text
    • https://vestol.bg/files/file/93473959399.pdfIn PDF document text
    • https://tirthmobile.com/wp-content/plugins/super-forms/uploads/php/files/fato2tjlsj005nmmu606nam552/xagenekokulubetop.pdfIn PDF document text
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/94aa76f81b8a96d9d0355522a12296b2/93838319581.pdfIn PDF document text
    • https://3dreamstudios.com/wp-content/plugins/super-forms/uploads/php/files/e4d822ae04171efe6bd37e6613855e30/toxofedinomur.pdfIn PDF document text
    • https://alutat.com/data/file/44964912906.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=english+made+easy+volume+3+pdfPDF 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_off0000d953.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD953 11184 bytes
SHA-256: edb33d91eb3588086473f7563c647769481968b53dbc7e377aee663e1f51ccdb
font_01_sfnt_off0000f319.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF319 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010b2b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B2B 17292 bytes
SHA-256: 94aa7bed2cd9661a809ba5e2551aae6f869a23457a1e0b0446f92b827d4909dc