Malicious PDF — malware analysis report

Static analysis result for SHA-256 1e3cf83b5f3c360b…

MALICIOUS

PDF

97.0 KB Created: 2021-08-07 01:52:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: de346ba95c5b0c2b35b0407002a4c95d SHA-1: 1d1aef32ae0bce16aa82bc927f00a9f62a5297c8 SHA-256: 1e3cf83b5f3c360b6039a137bbba945de28a7c4bb17ab81503fc5432f9684af8
96 Risk Score

Malware Insights

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

The PDF file contains a large number of embedded URLs, many of which point to compromised WordPress sites or disposable hosting. The ML classifier strongly indicates maliciousness, and the structure suggests a link farm designed to redirect users. The presence of multiple compromised CMS upload links further supports the malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://coolinterier.sk/upload/files/bewawevi.pdf In PDF document text
    • https://trvstore.com/userfiles/file/57536468931.pdfIn PDF document text
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/b6cdeff4dd4dd687e5df67c20bc099f2/lomufezesiwuzipijiwo.pdfIn PDF document text
    • http://www.suffaheducation.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073c4c4290b7---lojisile.pdfIn PDF document text
    • http://debschoen.com/userfiles/file/luwapin.pdfIn PDF document text
    • http://narcisse.sk/editor_uploads/files/52590900420.pdfIn PDF document text
    • http://cafesezony.ru/fck_editor_files/files/46352824645.pdfIn PDF document text
    • https://certifiedmoversinc.com/wp-content/plugins/super-forms/uploads/php/files/39c888409da0b5ac9c4fd6c6013e3aec/54343189350.pdfIn PDF document text
    • http://benetalent.com/upload/files/giguxurar.pdfIn PDF document text
    • http://www.jimenez-casquet.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f85d504049---wuteve.pdfIn PDF document text
    • http://sjhrz.com/images/upload/File/78278793636.pdfIn PDF document text
    • http://graham1978.com/clients/79565/File/jofumutanowudonilewid.pdfIn PDF document text
    • http://blackshirts1962.com/clients/f/f2/f245580d3072b78cda2271cf7a7e3f61/File/pivepevoriz.pdfIn PDF document text
    • https://archltginc.com/wp-content/plugins/super-forms/uploads/php/files/9fc4cf0e24ccde6d0089bbe94c838cf8/48933717803.pdfIn PDF document text
    • http://cen7dias.es/userfiles/files/vedelurel.pdfIn PDF document text
    • http://securitydirect.it/wp-content/plugins/super-forms/uploads/php/files/eea25b811065787c300de5b1bb7b2091/kefetukalob.pdfIn PDF document text
    • http://shinserviceodi.ru/wp-content/plugins/super-forms/uploads/php/files/b7ed5a37801e8f6dad28c862a8a25ac8/vofatupenobarefuwobele.pdfIn PDF document text
    • http://allegroescrow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160791695533f1---vowimetilojufop.pdfIn PDF document text
    • http://smartcookieacademy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b2f54bd196---kezefowejovebimub.pdfIn PDF document text
    • http://studioindelicato.com/userfiles/files/83705019272.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=do+you+italicize+article+titles+in+mlaPDF 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_off00011763.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11763 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00012f75.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12F75 17576 bytes
SHA-256: c147a5b0380d3e47e87cb6a1118c06ac77cd9a0aec2ededee68f840c44193200
font_02_sfnt_off00015dbf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15DBF 10664 bytes
SHA-256: 6f0f61a5f4b1aa282ae339ca06f737d967106aa52844da69c5c33700b46781b3