Malicious PDF — malware analysis report

Static analysis result for SHA-256 c57eb2a53e56335e…

MALICIOUS

PDF

73.6 KB Created: 2021-09-29 11:34:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 90db54bc0127d256c95b9136f825c222 SHA-1: 76b10e125b9d81d1c3cade692c44057914e05c4d SHA-256: c57eb2a53e56335e9373c7edf52588659e908a4e1e2acf8007c034c81bd2b4de
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, directing users to multiple external websites, some of which are hosted on compromised CMS uploads or disposable domains. The embedded URLs suggest an attempt to lead users to phishing or malware download sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://objets.immoweiss.lu/userfiles/files/59168807094.pdf In PDF document text
    • http://bonfiremadigan.com/uploads/fckeditor/file/59344251362.pdfIn PDF document text
    • http://leadingedgecorporate.com/user_images/file/13519406489.pdfIn PDF document text
    • http://sangjeom.com/userfiles/file///terebuvorepapulageviboja.pdfIn PDF document text
    • http://dobrasekacka.cz/userfiles/file/92217345734.pdfIn PDF document text
    • https://marblobaths.com/app/webroot/img/files/siwogobire.pdfIn PDF document text
    • https://xn----7sbbg1ddpkdc.xn--j1amh/uploads/files/98626342863.pdfIn PDF document text
    • http://biolabsrl.org/userfiles/files/kogepinupixejone.pdfIn PDF document text
    • http://www.ebsjosepirosamaria.com/wp-content/plugins/formcraft/file-upload/server/content/files/161404f17d1a10---5727551272.pdfIn PDF document text
    • http://cafesezony.ru/fck_editor_files/files/luriwomikolitogalefo.pdfIn PDF document text
    • http://2ds-creations.fr/userfiles/file/33736714602.pdfIn PDF document text
    • http://rfychina.com/upfiles/files/16322968927511.pdfIn PDF document text
    • http://lovesenergy.com/file/37925255283.pdfIn PDF document text
    • https://sellos-mecanicos.com/wp-content/plugins/super-forms/uploads/php/files/b54df08774e2affcec2e8b6aa8b2e89c/81293918941.pdfIn PDF document text
    • https://marthomaktrplrdiocese.org/ckfinder/userfiles/files/51864837206.pdfIn PDF document text
    • http://hzzxtl.com/UploadFile/file/20210905031130955.pdfIn PDF document text
    • http://matstravel.ru/userfiles/file/viwetinopudesumaxo.pdfIn PDF document text
    • https://alirezamirmohammadi.com/images/upload/files/58593839558.pdfIn PDF document text
    • http://trunghungplastic.com/luutru/files/kulizot.pdfIn PDF document text
    • http://wuyioutdoor.com/userfiles/file/fososesefida.pdfIn PDF document text
    • http://perfect-gallery.com/userfiles/file/67702853811.pdfIn PDF document text
    • http://raduzhniy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614c1890cd9c0---19083823937.pdfIn PDF document text
    • http://ladna.pl/user_images/file/16316926911.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=mcc+apn+settingsPDF 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b60e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB60E 10276 bytes
SHA-256: 4ef32403f3c5bca749cfb13dfeac5c4ed68d8df32e855d92580bc19d23f18e23
font_01_sfnt_off0000cd5a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD5A 19504 bytes
SHA-256: ffc9d84e48d45626d52aaec0a3e12876b84a98f7ae1ae0353579770196777ded
font_02_sfnt_off000100fb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100FB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1