Malicious PDF — malware analysis report

Static analysis result for SHA-256 7f896263fd4b7e42…

MALICIOUS

PDF

83.8 KB Created: 2021-07-13 17:11:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-15
MD5: 4aa1d4a98cd42820284fec7af9f31826 SHA-1: 7fcd451950c85a96a702b7f5b1f4d761606b5710 SHA-256: 7f896263fd4b7e42e815bdc1a648d2d3f2e1679c4f0fd5a2f0eacb51f962167c
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded links pointing to compromised WordPress sites and other disposable hosting, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the nature of the embedded links and the PDF structure align with techniques used to deliver second-stage payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://krisoc.ru/uplcv?utm_term=haroun+and+the+sea+of+stories+text+pdf PDF link annotation
    • https://b2cexpressdemo.com/userfiles/file/sinuta.pdfIn PDF document text
    • https://www.hungryalex.com/wp-content/plugins/super-forms/uploads/php/files/2dncgq38amiirg26dq4huj36o4/26964349337.pdfIn PDF document text
    • https://www.abaco-engineering.it/wp-content/plugins/formcraft/file-upload/server/content/files/16091253e1d9c5---86863193288.pdfIn PDF document text
    • http://mastera-mix.ru/ckfinder/userfiles/files/wuwewisiburenuzu.pdfIn PDF document text
    • http://bet-balance.com/userfiles/file/98700767560.pdfIn PDF document text
    • http://abacusnancy.com/userfiles/file/xaroxegemiwar.pdfIn PDF document text
    • https://okud-istra.hr/userfiles/file/1846591874.pdfIn PDF document text
    • https://graffitipaintstudio.com/wp-content/plugins/super-forms/uploads/php/files/52688ecff3294dc5393703ef6f13e6bd/benelumudi.pdfIn PDF document text
    • http://www.sunarnuricomuisvealisverismerkezi.com/wp-content/plugins/super-forms/uploads/php/files/6snqst900sfe5ef2b35u28aog0/xegat.pdfIn PDF document text
    • http://enjoybowlramenandpoke.com/uploads/files/94029771063.pdfIn PDF document text
    • http://boathousebrokerage.com/userfiles/file/51908852689.pdfIn PDF document text
    • http://bezpieczna-strefa.pl/wp-content/plugins/super-forms/uploads/php/files/32db9fd8a2b1654cb708f978a9420c3d/16187910189.pdfIn PDF document text
    • https://lecachet.fr/docs/files/25402010944.pdfIn PDF document text
    • http://fittbike.hu/files/file/tofoboxaxutaf.pdfIn PDF document text
    • http://goldnumber.info/userfiles/file/68817092820.pdfIn PDF document text
    • https://aimhc.com/userfiles/file/31836376942.pdfIn PDF document text
    • https://www.simplythebestevents.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1609e582e03986---31623073673.pdfIn PDF document text
    • http://thedewakohchang.com/image/upload/File/4134708987.pdfIn PDF document text
    • https://deedpoll.sg/wp-content/plugins/super-forms/uploads/php/files/6568b5b3fac634723643d9d4a296b60e/zufaxaferovedoruvafab.pdfIn PDF document text
    • http://www.maoles.com/wp-content/plugins/formcraft/file-upload/server/content/files/16092d0edac810---11241523433.pdfIn PDF document text
    • http://www.rkcomdesignservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608dac57d95dc---kiwugadesafadiv.pdfIn PDF document text
    • http://sgyscom.com/upload_fck/file/2021-6-18/20210618122452823075.pdfIn PDF document text
    • https://sesconbs.org.br/ckfinder/userfiles/files/97879927831.pdfIn PDF document text
    • http://vin-baietii.ro/ckfinder/userfiles/files/pukobemaruveletot.pdfIn PDF document text
    • http://dzbnf.com/upload/file///69796433253.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_off0000e59f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE59F 17104 bytes
SHA-256: d52ec37dfde15e399e91a35c29e514a3641fe03174ed4ad1e385e77b669cba36
font_01_sfnt_off00011133.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11133 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001294a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1294A 10740 bytes
SHA-256: fa2b1f5a759bda263c7effe78b395246bf58014e640af3af03abb5025156a09d