Malicious PDF — malware analysis report

Static analysis result for SHA-256 191abc02c7270358…

MALICIOUS

PDF

72.3 KB Created: 2021-06-17 19:13:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-12
MD5: dbb31b6bffed83559a5ce9ab1f50cfe8 SHA-1: b399d9f9a8832953063a3a82557d539e192f6a90 SHA-256: 191abc02c72703588a29b651422b2fe035da1ce7ba63f51d0acea1e211eab65f
96 Risk Score

Malware Insights

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

The PDF file contains a link farm with numerous external URLs, many hosted on compromised CMS upload directories. The ML classifier strongly indicates maliciousness, and the structure suggests the document is designed to redirect users to potentially harmful sites. The presence of multiple distinct hosts and UTM parameters points towards SEO manipulation or traffic distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • 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://crewmak.ru/uplcv?utm_term=the+8th+habit+website PDF link annotation
    • https://areshin.ru/wp-content/plugins/super-forms/uploads/php/files/2acb187e516c47a1f62cf913bf26fb5b/jelepana.pdfIn PDF document text
    • https://espiber.cl/images/uploadedimages/file/82422024025.pdfIn PDF document text
    • https://omomediacion.com/wp-content/plugins/super-forms/uploads/php/files/6175cb51e449603765bb8e28272f8d68/jegozesinoxapo.pdfIn PDF document text
    • https://monyetmesum.com/contents//files/bumifap.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/16087163cdca26---33203199700.pdfIn PDF document text
    • https://elbag.net/wp-content/plugins/super-forms/uploads/php/files/1efe6b91c24e3d926b84304ac7ec69cd/vekenenubomedefis.pdfIn PDF document text
    • http://fszhenjia.com/upfolder/e/files/20210529065510.pdfIn PDF document text
    • http://americanewbie.com/userfiles/file/xulexer.pdfIn PDF document text
    • https://www.traveltimevipp.com/wp-content/plugins/super-forms/uploads/php/files/f3d7cdc2d059764def045b313af06373/jagijava.pdfIn PDF document text
    • https://miamiuniquelimo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e41a377c80---62750021430.pdfIn PDF document text
    • http://www.luminicaambiental.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a7ecb07cc7---rajukalojebaregova.pdfIn PDF document text
    • https://b2cexpressdemo.com/userfiles/file/35754913156.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/16096997878308---nopepunawonaroxu.pdfIn PDF document text
    • https://www.onestopnaturalstore.ca/wp-content/plugins/super-forms/uploads/php/files/7i6q4ske34fmm38len82jae3sh/xafegawuxeg.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/16093f46023882---pilurusepoxajineduj.pdfIn PDF document text
    • https://n-zvuk.ru/upload/file/piwafonejajeriselik.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d2e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD2E1 4592 bytes
SHA-256: 1f16fc0a3353b31f2cfb9be4bae9d701f7ede1eb25c059f11ac1f6858b56045c
font_01_sfnt_off0000e299.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE299 10524 bytes
SHA-256: 5a3f3f91245ada22309bbba389d11cb05b0970662714d72ee78ac074561355da
font_02_sfnt_off0001066a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1066A 4324 bytes
SHA-256: a542ec26cea93e049a2e27cd59b1347dd9bbdea13775fd7b822b3c2b3136116f