Malicious PDF — malware analysis report

Static analysis result for SHA-256 45b290f153ff8da2…

MALICIOUS

PDF

80.0 KB Created: 2021-09-15 16:16:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: e4a223adda8e89adb0085a6997bd619d SHA-1: 4f735315c6ad3ed056625a7cf9747f1f2e5107cb SHA-256: 45b290f153ff8da294cf9c39bfc7c97d91c4e77765e478cf1dc15edd7082c4a4
104 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and multiple external URIs, many of which point to compromised CMS uploads or disposable hosting. These links are structured as a link farm, suggesting an attempt to direct users to download other files, likely malicious payloads. The ML classifier strongly indicates malicious intent, and the overall structure points to a downloader or redirector pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://philabc.ru/uplcv?utm_term=chess+royale+mod+apk+unlimited+money PDF link annotation
    • http://smingames.com/ckfinder/files/2988975891.pdfIn PDF document text
    • https://alamansyria.com/userfiles/file/biwove.pdfIn PDF document text
    • http://dvg.asia/ckfinder/uploadfiles/files/65107517869.pdfIn PDF document text
    • https://byocamacho.com/ckfinder/userfiles/files/12659718845.pdfIn PDF document text
    • http://reliancefla.com/admin/images/file/95858801890.pdfIn PDF document text
    • http://sjmhospital.org/files/js/ckfinder/userfiles/files/napeborifolowafoteweva.pdfIn PDF document text
    • http://videotour24.com/data/fckupload/file/33551682579.pdfIn PDF document text
    • http://coral-travel66.ru/admin/ckfinder/userfiles/files/fuvajidu.pdfIn PDF document text
    • http://hstairan.com/FCKeditor/editor/filemanager/connectors/php/userfiles/file/nuwef.pdfIn PDF document text
    • http://objets.immoweiss.lu/userfiles/files/45858553115.pdfIn PDF document text
    • https://bahamianbrewery.com/ckfinder/userfiles/files/fuxufavota.pdfIn PDF document text
    • https://ecoinkworld.com/wp-content/plugins/super-forms/uploads/php/files/5a2dc78432f165033afb7b4be28a1418/73920636785.pdfIn PDF document text
    • http://conservationenergy.com/wp-content/plugins/formcraft/file-upload/server/content/files/161319f6c8551b---buletun.pdfIn PDF document text
    • http://xn--9i1b14l32gg2dsybq3b.com/upload/fckeditor/file/6239495991.pdfIn PDF document text
    • http://www.aportecnica.com/imagenes/editor/file/76913943481.pdfIn PDF document text
    • http://ideviceplus.be/app/webroot/files/userfiles/files/16498780591.pdfIn PDF document text
    • http://vibrator4you.cz/UserFiles/File/81001675588.pdfIn PDF document text
    • https://barrierball.cl/ckfinder/userfiles/files/91934652853.pdfIn PDF document text
    • http://co-wemart.com/careeruserfiles/file/3297152686.pdfIn PDF document text
    • https://rhythmcprandfirstaid.com/wp-content/plugins/super-forms/uploads/php/files/444302a83f742cbd8e7bf4158c7a4dec/lenogajeripanuwof.pdfIn PDF document text
    • http://mocphatreal.com/assets/images/ckfinder/files/sofobevanijupe.pdfIn PDF document text
    • http://trustarshida.co/cache/fck_files/file/wakadufefivede.pdfIn PDF document text
    • http://taikenplan.jp/ckfinder/userfiles/files/10379205213.pdfIn PDF document text
    • https://asiahealthcaredentalcentre.com/ckfinder/userfiles/files/xisawisuwewakofutaji.pdfIn PDF document text
    • http://acrclubinversores.com/files/galeria/files/fiximewuxujonomov.pdfIn 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://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_off0000cff6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFF6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e808.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE808 18820 bytes
SHA-256: d276046864bb3349222a9215639a11471b95c16c857e3461873ecf30e2535b9c
font_02_sfnt_off000118c8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118C8 10992 bytes
SHA-256: 48378438904e745e71852e93148347ba78cff35d3a76e920a49c0f5e61ac5888