Malicious PDF — malware analysis report

Static analysis result for SHA-256 7bc43e1070178439…

MALICIOUS

PDF

89.4 KB Created: 2021-07-05 08:28:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-17
MD5: 50ac363cf204aed380104308ab980f4e SHA-1: 0aa7d2160785b2b49cacd003ba82ea61c1a3dcd7 SHA-256: 7bc43e1070178439e30704a9710e1a6b31b4b7c5b6122efc9c66bb4cd59b605a
156 Risk Score

Malware Insights

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

The file is identified as malicious by ClamAV and an ML classifier. Heuristics indicate it functions as a link farm, with many URLs pointing to compromised WordPress sites. The PDF likely serves as a lure to redirect users to malicious content, potentially for phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

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 http://ecbpolska.pl/wp-content/plugins/super-forms/uploads/php/files/4679554360ceba77cb6637c9fea834fd/50874440704.pdf In PDF document text
    • https://cedarcreeksauce.com/wp-content/plugins/super-forms/uploads/php/files/5521a001bc8c6eef237b632f44189d97/20565478302.pdfIn PDF document text
    • http://asesoriagarpe.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c6d0981b94---fivanapi.pdfIn PDF document text
    • http://math-talk.kr/wp-content/plugins/super-forms/uploads/php/files/gau68kvj9rot01qr41jnrtsbdo/63849314917.pdfIn PDF document text
    • http://www.k-24.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a1983b4d417---88674931421.pdfIn PDF document text
    • https://abril.pe/wp-content/plugins/super-forms/uploads/php/files/fv0ujq7ego9shkhgab0ir0gns0/90865229708.pdfIn PDF document text
    • http://www.segurosfacility.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160840ffa645cc---16154687662.pdfIn PDF document text
    • http://nuyewrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/669464e6ca7bed4c878a2fddf783a2e2/mowobuzuluzo.pdfIn PDF document text
    • https://derey.nl/app/webroot/files/userfiles/files/5107880894.pdfIn PDF document text
    • https://kvartira-zalog.ru/wp-content/plugins/super-forms/uploads/php/files/3cb48467b1cca1d992e5eef62b1ad6cc/xoxifavatatozi.pdfIn PDF document text
    • http://www.elsecretodelolivo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d4045f3672---disilasotivogabifamirip.pdfIn PDF document text
    • http://asesoriagarpe.com/wp-content/plugins/formcraft/file-upload/server/content/files/160db7dd25cb8f---3606120351.pdfIn PDF document text
    • https://quickonboarding.com/wp-content/plugins/super-forms/uploads/php/files/beac86b0c66fde34da59307eab949485/26860758361.pdfIn PDF document text
    • http://www.majoriscambio.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609d3ddf3803c---90730142916.pdfIn PDF document text
    • http://leaguengn.com/userfiles/file///4379434789.pdfIn PDF document text
    • http://mwflower.com/upimagesfile///xufejotegijexek.pdfIn PDF document text
    • https://ukdirectremovals.com/wp-content/plugins/super-forms/uploads/php/files/eb074cb9eae16712cc9fe7152d06e2da/43743351938.pdfIn PDF document text
    • http://europeanprofservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160917edc7c098---54638860346.pdfIn PDF document text
    • http://www.expo-hotel.com/english/wp-content/plugins/formcraft/file-upload/server/content/files/160a60eaa9c8cb---54944161012.pdfIn PDF document text
    • http://assessmentinsight.com/ckfinder/userfiles/files/favudobaxudipelunetof.pdfIn PDF document text
    • http://intechsol.kz/wp-content/plugins/formcraft/file-upload/server/content/files/160a4022e6863f---wuxezikumomotazifeg.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=pdf+with+links+examplePDF 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_off0000f584.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF584 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010d96.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D96 18848 bytes
SHA-256: f9d11ff91789bfbe022d71601c6942d150ca95b0a211f42ad02cc36ae31750f9
font_02_sfnt_off00013e5c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13E5C 10824 bytes
SHA-256: ab28cfd7da6c2d67d55ca91b7a9ee222408e4b8dadedf746aeb9696b0d918c78