Malicious PDF — malware analysis report

Static analysis result for SHA-256 f31ee9401aa635f2…

MALICIOUS

PDF

85.1 KB Created: 2021-07-01 21:56:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 20bd572d211ed1475fcbadac87a0cf3b SHA-1: b68db52a65d3c975407102b09a417cf34ac70279 SHA-256: f31ee9401aa635f28cf29fe0afdb3e20e77787662674f0ec1aac59718a1ee05e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links to external PDFs hosted on compromised WordPress sites, suggesting a link farm designed to distribute malware or conduct phishing. The presence of embedded URLs and the nature of the heuristics indicate an attempt to redirect users to malicious content, likely disguised as legitimate downloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 https://www.conkite.com/wp-content/plugins/super-forms/uploads/php/files/2aa12a7ab858792c1a85efe18b524995/digupomubobexoz.pdf In PDF document text
    • https://www.siemers-deutschmann.de/wp-content/plugins/super-forms/uploads/php/files/efnfilvgg412d8r8c04mu6qdtc/rekumuneji.pdfIn PDF document text
    • http://ahlhy.com/uploads/file/141929369423.pdfIn PDF document text
    • http://dzbnf.com/upload/file///47340897124.pdfIn PDF document text
    • https://alate.org/admin/fckeditor/editorfile/rijolufafofu.pdfIn PDF document text
    • https://kovosluzba-praha.cz/res/file/21331220083.pdfIn PDF document text
    • https://insights3.com/wp-content/plugins/super-forms/uploads/php/files/83129380a69217bbec8bc32ffa1d7737/sawonobadivu.pdfIn PDF document text
    • https://webgirls-studio.com/wp-content/plugins/formcraft/file-upload/server/content/files/160be0a628ecad---mekisuboriber.pdfIn PDF document text
    • http://artecgroupservices.com/imagenes/file/zasoludan.pdfIn PDF document text
    • https://tidaksusah.com/contents//files/32297790032.pdfIn PDF document text
    • http://wsm.hk/images/uploadfiles/file/kitevimonanegadebakis.pdfIn PDF document text
    • http://krakow4you.pl/krakow/files/81882361711.pdfIn PDF document text
    • https://lawina-radom.pl/files/file/82265330224.pdfIn PDF document text
    • https://dentinale.eu/wp-content/plugins/super-forms/uploads/php/files/36fe598ff3f3e872c6bfd556e2c135c1/33895318644.pdfIn PDF document text
    • http://visualpaint.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c79a3929c5---fixasovomuzinosune.pdfIn PDF document text
    • https://www.tessilgiada.it/wp-content/plugins/formcraft/file-upload/server/content/files/160a6af894d6bd---28303777812.pdfIn PDF document text
    • https://www.limratechnologies.net/wp-content/plugins/formcraft/file-upload/server/content/files/160c4770c3a84d---foguwoxotegapikipiwawoput.pdfIn PDF document text
    • https://aitalk.vn/upload/files/90997291966.pdfIn PDF document text
    • https://rfcorporation.net/wp-content/plugins/super-forms/uploads/php/files/28e00d7f94dbe389b0d3cd34ad8f9073/kigetabizuburumik.pdfIn PDF document text
    • http://feriaalainversa.com/uploaded/files/muvikuf.pdfIn PDF document text
    • http://trackeg.com/en/wp-content/plugins/formcraft/file-upload/server/content/files/1607049ba8c966---lubogekukelibawasi.pdfIn PDF document text
    • https://www.vigo.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160a4a90a04866---65627236386.pdfIn PDF document text
    • https://asaptransfers.co.uk/wp-content/plugins/super-forms/uploads/php/files/b7olkf0i2j5e076635bmgb6b60/dezivu.pdfIn PDF document text
    • https://stakeoutllc.com/wp-content/plugins/super-forms/uploads/php/files/7e4fbe01107c34e5087dd1b4a41c5b36/76081737482.pdfIn PDF document text
    • https://xn--80aaaglcftt5alesfkk7f.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/d45822727f51681664619a2380df3bf9/balitibividu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=resume+template+download+for+engineering+freshersPDF 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_off0000e6ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6EA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ff01.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF01 11176 bytes
SHA-256: d5ffabcb3332af58f9323796ff94a458939ec44cfc69f6a61463991689f63b58
font_02_sfnt_off000118cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118CB 17456 bytes
SHA-256: 47253570527a22a204ed156cb0370aaddb8ddc95c53ea390b4d3a1725b671b80