Malicious PDF — malware analysis report

Static analysis result for SHA-256 810ac6da633f4ba4…

MALICIOUS

PDF

76.0 KB Created: 2021-06-25 12:03:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7f0c7cdd2e448bd44d16a78edcd3b1b0 SHA-1: df1af56645b8e0a116d7787624a64b724063631f SHA-256: 810ac6da633f4ba47b20094bc34c8009e9c90e2c7111532df4fee37cb9beac11
176 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, containing numerous URLs pointing to various domains, many of which appear to be compromised or disposable hosting. These links likely lead to phishing pages or further malware downloads, aligning with the 'Spearphishing Attachment' technique. The presence of multiple external URIs and a link farm structure suggests an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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://oniceh.ru/uplcv?utm_term=dead+town+apk
    • https://feniks9.ru/ckfinder/userfiles/files/75399724013.pdf
    • http://sip7.online/wp-content/plugins/super-forms/uploads/php/files/2c7309ba111a23a19a3b2231e97e8bfb/bizidazunanuditejesowimu.pdf
    • https://www.kunapak.com/wp-content/plugins/super-forms/uploads/php/files/1g7ad4o04fug4b6qlhchpdvn0p/xupovamifigoxegemamizide.pdf
    • http://dominoliberec.eu/images/file/files/49882308983.pdf
    • http://www.grundys.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160d3c449f337e---bixijamivanakuxewagolok.pdf
    • http://79.170.40.182/boothtastic.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b4d5dac6745---gipulebefewomodutide.pdf
    • https://ateneoarbonaida.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d9528c7575---82360997854.pdf
    • http://elonsummerstorage.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088e521af340---66725664570.pdf
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/ujr3409jj967io3ohapmsgo854/zenanemosezan.pdf
    • https://adepotcustom.com/UploadFiles/file/20210428135309163.pdf
    • https://polskieplytki.com/wp-content/plugins/super-forms/uploads/php/files/6ddbc67d0284482afd598bd06b0a6766/99654722852.pdf
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081592d2ab54---xuneguxowulajoxidad.pdf
    • http://urbanconstructions.org/images/uploadedimages/file/fipefixedirobip.pdf
    • http://driver-jazda.pl/upload/file/nudikud.pdf
    • http://vasvaripalmuzeum.hu/upload/file/sabino.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c55a.bin
118654650fe40dc804f222f706c1736c004c6b094078d8048f9186fb5fd85419
pdf-font-stream PDF embedded font (sfnt) at offset 0xC55A 18212 bytes
font_01_sfnt_off0000f323.bin
8e17a2cca2c9bfea23a721f1097d1e7ae379526141e897880a5b4f4968a380cd
pdf-font-stream PDF embedded font (sfnt) at offset 0xF323 10160 bytes
font_02_sfnt_off00010a09.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10A09 16792 bytes