Malicious PDF — malware analysis report

Static analysis result for SHA-256 90a7df6effac74f3…

MALICIOUS

PDF

105.8 KB Created: 2021-07-22 12:45:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 085e87da33d5ecd6f5683b8da34577d0 SHA-1: ce69006630dbc52419f6896e3c569f77c4b2df73 SHA-256: 90a7df6effac74f333aadbf1718fec7803c73378071f12bd9e2b57cf161ef1c8
96 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to compromised WordPress sites, suggesting an attempt to redirect users to malicious content. The ML classifier also flagged this PDF as malicious with high confidence. No scripts were extracted, limiting the analysis of direct execution vectors.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9822

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 http://posekatzahradu.cz/files/file/38124196251.pdf In PDF document text
    • https://admonks.ru/wp-content/plugins/super-forms/uploads/php/files/abde9e6a6da5b669131bcc34afa3d0f4/vuzex.pdfIn PDF document text
    • https://elitteaccesorios.com/wp-content/plugins/super-forms/uploads/php/files/rebqfr624kfrh8962nvg8h7fcq/netinaxuxikokiretekanulol.pdfIn PDF document text
    • https://wcdt.co.th/wp-content/plugins/super-forms/uploads/php/files/5a0id6o3k7b1k4dq6j5i7inubn/wubumi.pdfIn PDF document text
    • https://canadianrelocation.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607857d64a5cc---94818765210.pdfIn PDF document text
    • https://anctools.com/ckfinder/userfiles/files/xonepejimapekojuwakel.pdfIn PDF document text
    • https://3dreamstudios.com/wp-content/plugins/super-forms/uploads/php/files/d6af7873362944eae904eada3d37c210/gutikofuzilavifofozo.pdfIn PDF document text
    • http://ophirtonhotel.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160ce87a090c58---44724283892.pdfIn PDF document text
    • https://www.nordatec.com/wp-content/plugins/super-forms/uploads/php/files/pn0011ur4ao16iodppckt4tkbl/nozedufatafeli.pdfIn PDF document text
    • https://terryhaas.com/wp-content/plugins/super-forms/uploads/php/files/70b564dc4d5d49f5b5a49d100103e77e/45216563384.pdfIn PDF document text
    • https://samarpanbharat.org/trila/userfiles/file/gujasivusuk.pdfIn PDF document text
    • http://terwaarde.be/ckfinder/userfiles/files/pizilifufejodowenajof.pdfIn PDF document text
    • http://www.pilonidalsinus.gen.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16083c0d643210---12867787520.pdfIn PDF document text
    • https://mattweidnerlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d5c1d054162---41985484063.pdfIn PDF document text
    • http://ccforum.kr/uploads/file/1624298118.pdfIn PDF document text
    • http://renovfab-menuiserie.com/userfiles/file/43435477996.pdfIn PDF document text
    • http://amphorabeautyclub.com/campannas/file/kiwovosuwuman.pdfIn PDF document text
    • http://adams-gold.ru/archive/image/file/46091712750.pdfIn PDF document text
    • https://tractorpulling-emmeloord.nl/upload/file/43478015430.pdfIn PDF document text
    • http://abnicum.com/files/file/jivakazuramoruzakeru.pdfIn PDF document text
    • http://wakingbeauty.com/wp-content/plugins/formcraft/file-upload/server/content/files/160758043c4e8a---samefazofewize.pdfIn PDF document text
    • https://coffeetuanvang.com/Images_upload/files/17012615872.pdfIn PDF document text
    • https://kachhiproperties.com/wp-content/plugins/super-forms/uploads/php/files/ku029674gaiemjfbgt4ihd8785/78575153913.pdfIn PDF document text
    • http://houstontca.org/Content/uploads/files/dizatiwakede.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=pep+bakehouse+and+coffee+shopPDF 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 5

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_003_off0000f345.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0xF345 18428 bytes
SHA-256: d9536d663ccecbe62003f54334dc0df9825c0d1cdb270ef67e79c793df8615da
font_01_sfnt_off00011163.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11163 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001297a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1297A 10716 bytes
SHA-256: 9e58a0c3a0b2fd967211e06f0735574a7a4ee6e6b21c99f185e5eeaa340bf266
font_03_sfnt_off000141ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x141CE 4040 bytes
SHA-256: 5accd28b93f88256231765d54412dfb73b7c8b89e0db92651776be48329af4d6
font_04_sfnt_off00015112.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15112 29136 bytes
SHA-256: cc161426104913e158d0c8d19ae0d848a74ffd64cb4a68cdd226b43a8353e49b