Malicious PDF — malware analysis report

Static analysis result for SHA-256 763238debde394de…

MALICIOUS

PDF

88.2 KB Created: 2021-06-28 03:43:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 53ac108fad1a71a981932470d9dfdfb6 SHA-1: d2942396dd4cb04a3aced1c5a0c158b3a747798e SHA-256: 763238debde394dea345c6bedee7d797381ec5e28005b12cff6d79c221cd829d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links pointing to compromised WordPress upload directories and disposable hosting, suggesting a link farm designed to redirect users to malicious content. The PDF structure itself is heavily obfuscated, and while no scripts were explicitly extracted, the presence of numerous external URIs and the overall detection profile strongly suggest it's part of a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://www.ediliziaindustriale.com/wp-content/plugins/formcraft/file-upload/server/content/files/160771ff54612b---xorugonujona.pdf In PDF document text
    • https://www.siemers-deutschmann.de/wp-content/plugins/super-forms/uploads/php/files/vl6v4lds4aho43ebpr29bqo1fk/87877140580.pdfIn PDF document text
    • https://angelsforwarriors.org/userfiles/files/gikoxugakefofifizubewur.pdfIn PDF document text
    • http://lilit-realty.com/wp-content/plugins/super-forms/uploads/php/files/ntvichl5p45m1taisnadk4t0l0/jedigobowapilogut.pdfIn PDF document text
    • https://www.numberoneporthill.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1609e75ea18b8f---82720587575.pdfIn PDF document text
    • https://www.glasswindowequipment.com/wp-content/plugins/super-forms/uploads/php/files/c109aac1c9ab34cb9f9ddf2552cc4924/73964966981.pdfIn PDF document text
    • http://www.mmalappeenranta.com/tiedostot/files/78284141945.pdfIn PDF document text
    • https://www.lokalesichtbarkeit.de/wp-content/plugins/super-forms/uploads/php/files/unbncdsbo22iu4s37m2otrpk81/84286335076.pdfIn PDF document text
    • https://superpart.com/files/83556191792.pdfIn PDF document text
    • https://kes-stv.ru/wp-content/plugins/super-forms/uploads/php/files/d9ece3ccdf7ec68b2916ec90ba0344be/mugeta.pdfIn PDF document text
    • https://jodhpurtravels.com/nbloom/fckuploads/file/povuwa.pdfIn PDF document text
    • https://microfocus-realize2020mea.com/wp-content/plugins/super-forms/uploads/php/files/eacb4a2372be02c2171a03d6312f3704/59963079632.pdfIn PDF document text
    • https://qualitycountscleaning.com/wp-content/plugins/super-forms/uploads/php/files/6b9d0b0b87438750e06dca066d6c2923/jetabonu.pdfIn PDF document text
    • https://nanyangtextile.com/userfiles/file/wataruvakazexewokeje.pdfIn PDF document text
    • http://exactblue.com/wp-content/plugins/formcraft/file-upload/server/content/files/160927fff99177---52777579975.pdfIn PDF document text
    • https://skyzoan.com/cake/beta/userfiles/file/farobelilaloramojeda.pdfIn PDF document text
    • http://cetinelektrik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1606c86347cd16---kapegaseditone.pdfIn PDF document text
    • http://admio.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16079e61769841---guzesupilijanemi.pdfIn PDF document text
    • https://ahi.com.ua/wp-content/plugins/super-forms/uploads/php/files/978d055552619b5749b967f01b140219/bozulubemopugulo.pdfIn PDF document text
    • http://asalsold.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608fec9a93518---bapex.pdfIn PDF document text
    • http://tanriovermensucat.com/uploads/genel/files/jidekokonezejemagokeguwof.pdfIn PDF document text
    • https://iamtimeshare.com/userfiles/file/41852311905.pdfIn PDF document text
    • http://kcde.kr/userfiles/file/fumujis.pdfIn PDF document text
    • https://rmissio.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1607c3e6ac1cb6---1399785122.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=conflict+theory+on+educationPDF link annotation
    • https://mediaget.com/userfiles/files/84047969700.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_off0000f35d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF35D 17868 bytes
SHA-256: d80844735bbe998e75a72673d36e69702ef55d3a5fef0ea01f4aa2a299029f73
font_01_sfnt_off00012169.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12169 10648 bytes
SHA-256: 8eaa90d1ab7d43aba40ff7c85d1819f0be53299f8d4b3a6b9112a35397445df9
font_02_sfnt_off000139c3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x139C3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1