Malicious PDF — malware analysis report

Static analysis result for SHA-256 31874ec7e0a797ff…

MALICIOUS

PDF

114.9 KB Created: 2021-07-01 22:12:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4e4b9d9e4a0864e5f8b0c79ac6f42392 SHA-1: e6832371342ac957c030b8c6212b992eb45e5e2e SHA-256: 31874ec7e0a797ff1b23f2ef30151e7c362c648bf1e5e3e5480e771babf73a33
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs pointing to various domains, many of which appear to be compromised or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution through these links. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' further supports the interpretation of this PDF as a malicious link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9950

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 https://allytemp.ru/uplcv?utm_term=battle+realms+manual
    • http://barcelonasixtytwo.com/userfiles/file/belakive.pdf
    • https://clubforeducation.com/FCKeditor/userfiles/file/rojanezonawutilola.pdf
    • https://kompaspt1.com/contents//files/23573200315.pdf
    • http://verypool.cn/images/upload/File/somusobavelizidok.pdf
    • https://roadtoring.com/wp-content/plugins/super-forms/uploads/php/files/9b1bbb4502a63efb92127eb937a08313/xonaxomipenikinulera.pdf
    • http://cukiernia-waltar.pl/qcms/userfiles/file/jujavuwukozuf.pdf
    • http://archerelectricsupply.com/userfiles/file/35892335173.pdf
    • https://mbzl-pro.xyz/web/img/podborky/files/99371381542.pdf
    • https://wacee.net/wp-content/plugins/formcraft/file-upload/server/content/files/16075aa3a61ddb---1500974236.pdf
    • http://training-solutions.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160a78ff0ae09b---38507352256.pdf
    • http://iccj.jp/images/uploads/fckeditor/file/59439692210.pdf
    • http://www.altrus.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160a08b5411d4e---73889703824.pdf
    • http://sunnysolutions.it/uploads/assets/file/totexodaxufiberebi.pdf
    • https://www.energetisch-therapeut-estie.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b310d1da241---3576201451.pdf
    • https://almuhja.net/ckfinder/userfiles/files/59525428972.pdf
    • https://bikinibody.be/wp-content/plugins/super-forms/uploads/php/files/36ehe8lgnp75qq9evs1thcdvld/vepesirevitovapok.pdf
    • http://www.amedna.com/userfiles/files/lomeniv.pdf
    • https://lawpropertyconsultants.co.uk/wp-content/plugins/super-forms/uploads/php/files/nr5g2nnd7r6pehjttvqjeselcc/62697985056.pdf
    • http://standartbio.com/fckfiles/file/58738560243.pdf
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/onsieui4u6ihkjk864k0j57655/20086101288.pdf
    • http://kentcliffordreunion.com/clients/a/aa/aa84b18e55fac3ff3c25336c5005d9e5/File/22382834038.pdf
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/5juv4f572n8j00tangihbaeu1o/75509678059.pdf
    • http://mattstergamer.com/wp-content/plugins/super-forms/uploads/php/files/ppmau28nk6susmmm82t1daidlb/46263395503.pdf
    • https://www.ibyservice.com/wp-content/plugins/super-forms/uploads/php/files/c7019fb02177a77fa0217a8927b14d0b/nizevofarunenarazo.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00015de7.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x15DE7 16792 bytes
font_01_sfnt_off000175fe.bin
9844dd1d1141df137290bc026e7430c50b73b5d702dd90fc229f5241669c9a1e
pdf-font-stream PDF embedded font (sfnt) at offset 0x175FE 10212 bytes
font_02_sfnt_off00018ced.bin
945737a8a501c7f83218e9fcd9e60f46c53c0d4bd15b96bda4f939e039939528
pdf-font-stream PDF embedded font (sfnt) at offset 0x18CED 18608 bytes