Malicious PDF — malware analysis report

Static analysis result for SHA-256 9612c6b67ce3ded7…

MALICIOUS

PDF

86.9 KB Created: 2021-06-29 21:41:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: adce9858b691e048df80ed98420f3be2 SHA-1: e45719eeb5da9afb34844d72b764a4d58122f27f SHA-256: 9612c6b67ce3ded7e1cb80b38ad1800ac0d49949100015469a516332bc293b97
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier strongly flagged this PDF as malicious, and the heuristic firings confirm the presence of external URI links and a link farm strategy. The document body is heavily obfuscated and unreadable, providing no direct content-based clues.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://inwebjor.ru/uplcv?utm_term=physical+education+class+11+practical+file+pdf PDF link annotation
    • https://www.msolartop.cz/wp-content/plugins/formcraft/file-upload/server/content/files/160a2274404f0b---35339366899.pdfIn PDF document text
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/oibjbktkujluff4kuglui87n11/89855062361.pdfIn PDF document text
    • http://amuseonline.com/absite/userfiles/file/lirazugaro.pdfIn PDF document text
    • https://medicinasolidale.org/wp-content/plugins/super-forms/uploads/php/files/1cd98e42ba6b3c8991ff80e12c90e98d/36894640106.pdfIn PDF document text
    • https://rubin2000-distribuitorshop.ro/userfiles/file/3667541438.pdfIn PDF document text
    • http://escolacaritas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606fb987054b7---xonezukidadubujixofo.pdfIn PDF document text
    • http://chupanhnoithat.vn/upload/files/96495182225.pdfIn PDF document text
    • https://razvozka24.ru/wp-content/plugins/super-forms/uploads/php/files/e81bbf912e53b3753101254664c0f8e9/tivujolozodurijunoto.pdfIn PDF document text
    • http://livinglearningandworking.org/clients/e/e0/e05af8355f71d8da3aa90f500b9284b3/File/41355170807.pdfIn PDF document text
    • http://cosmic-kino.ru/sadm_files/73184921095.pdfIn PDF document text
    • https://bursaceviritercume.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608cfcab38a27---52301930237.pdfIn PDF document text
    • https://tucsonhomewindowtint.com/wp-content/plugins/super-forms/uploads/php/files/b0f1e4cfc0fc60242c700cde446a0996/23603813396.pdfIn PDF document text
    • https://cremeconferences.com/wp-content/plugins/super-forms/uploads/php/files/6e35a99b1c669fff71c016a57fd1a95c/72355622530.pdfIn PDF document text
    • https://alihuata.com/userfiles/file/40978933561.pdfIn PDF document text
    • http://exactblue.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e7a347e691---pixosofora.pdfIn PDF document text
    • http://nnk.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1607ce4c335ac5---71512913988.pdfIn PDF document text
    • https://advancedcheckcashadvance.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a22ce80c671---zaxin.pdfIn PDF document text
    • https://veglifekc.org/wp-content/plugins/super-forms/uploads/php/files//55208891576.pdfIn PDF document text
    • https://pinotcar.com/wp-content/plugins/super-forms/uploads/php/files/ece9ad919c4c9b04786925cd1b22aebe/81930331036.pdfIn PDF document text
    • https://www.pfgpartners.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607248f1bf9be---boridemidemezavo.pdfIn PDF document text
    • https://118highschool.am/wp-content/plugins/super-forms/uploads/php/files/488573f41f496c23e306786a52eb8cdd/vodumiraxezirasenosiz.pdfIn PDF document text
    • http://sintellect.ru/Repository/file/wakadobanef.pdfIn PDF document text
    • http://juha.be/_files/file/pudoruku.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/c1j3drsouku79vt50nf2ckb6j2/79103013895.pdfIn PDF document text
    • http://www.platformliften.info/wp-content/plugins/formcraft/file-upload/server/content/files/160c22fd895de0---92334414236.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_off0000ec4e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC4E 10984 bytes
SHA-256: 3f7a903ed6bb6a7b05c446827a085c1406b0c82a18e49f8b158b259f6a827470
font_01_sfnt_off000105d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105D0 18192 bytes
SHA-256: de117fcfec9a3adcb95d29386e0550d897e0a42132ba96b777d77d282cac801a
font_02_sfnt_off000135f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x135F5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1