Malicious PDF — malware analysis report

Static analysis result for SHA-256 62a4cf49d0bd72ca…

MALICIOUS

PDF

81.9 KB Created: 2021-09-06 10:57:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: f3ae2d364ceac7c0952245058fb8074b SHA-1: 588ad9381bba41e287506f37376efde793e07f5c SHA-256: 62a4cf49d0bd72cac0aebb0eac88b494bb6bbf959de91a7f9d8607fcee39e918
96 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many hosted on compromised WordPress sites or disposable domains, indicating a link farm. The ML classifier also flagged this PDF as malicious. The primary purpose appears to be directing users to external sites, potentially for SEO spam or to host further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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://cructi.ru/uplcv?utm_term=operation+of+two+stroke+engine+pdf PDF link annotation
    • http://reklama-v-sochi.com/ckfinder/userfiles/files/dizusadibil.pdfIn PDF document text
    • http://papaicountrylodge-longstay.com/user_img/files/97198858106.pdfIn PDF document text
    • http://cleannshieldflorida.com/wp-content/plugins/super-forms/uploads/php/files/3b2dcc1434bbea7ec7c02db020023ad0/94388556423.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/c2e1e822eee330dad2b18069d5e24030/gegebif.pdfIn PDF document text
    • https://kvartira-zalog.ru/wp-content/plugins/super-forms/uploads/php/files/66f9e1ca9dc28fa8217be2e9b80285e3/pigazutolowo.pdfIn PDF document text
    • https://edukiya.com/wp-content/plugins/super-forms/uploads/php/files/b4a701a1e929f3484780d5be438fa0a1/pulewitobamapizijurune.pdfIn PDF document text
    • https://www.verimevzabavu.cz/ckfinder/userfiles/files/7871934947.pdfIn PDF document text
    • http://beetsom.com/PROGRAM_FCKeditor_UserFiles/file/144935681160bacfec46540.pdfIn PDF document text
    • https://retentionstudentexperience.com/wp-content/plugins/formcraft/file-upload/server/content/files/160961eb1774ae---jivegodifa.pdfIn PDF document text
    • https://eurocomm-italia.com/file/10586037247.pdfIn PDF document text
    • https://heykidsletscook.info/wp-content/plugins/super-forms/uploads/php/files/a42191a95eef1ef3a710127e35603d55/sifigexajizoxutomofagukal.pdfIn PDF document text
    • http://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/a35ecc56161540de039d22ede4e78a80/85341215141.pdfIn PDF document text
    • http://teifsepahan.com/files/file/rivufiviwedexajofukexevo.pdfIn PDF document text
    • https://berbagiangka.com/contents//files/21647178456.pdfIn PDF document text
    • https://bustotoronto.com/userfiles/file/gevefekezopova.pdfIn PDF document text
    • http://oawebserver.com/piceditor/file/luvojukitomoz.pdfIn PDF document text
    • https://dienlanhhonganh.com/images/pic/file/15353989281.pdfIn PDF document text
    • https://chingchia.com/uploads/files/202108261804333773.pdfIn PDF document text
    • http://viaterrestre.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160796befa7497---54949623262.pdfIn PDF document text
    • http://baikalspring.ru/ckfinder/userfiles/files/bajoputewetuzefuwev.pdfIn PDF document text
    • http://jvcc.cn/ckfinder/userfiles/files/2106022151598179060gyft.pdfIn PDF document text
    • http://zekidilektekstil.com/images_upload/files/91312117193.pdfIn PDF document text
    • http://artediapharma.com/upload/files/76387630207.pdfIn PDF document text
    • http://recamonde.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160943411293d8---28768059646.pdfIn PDF document text
    • http://conservationenergy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608d0c3882dd4---47465723610.pdfIn PDF document text
    • http://meyergarden.com/ckfinder/userfiles/files/76370089383.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_off0000dc61.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC61 17444 bytes
SHA-256: 715e1141e6bb98660fc397021b3503ed76a9b3fe6bd1ac66bd52dcb01e3af54c
font_01_sfnt_off000108f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108F6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001210d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1210D 10828 bytes
SHA-256: c4c3533902a7d3bf878e36ffb5b26ca97d2a50c173462ca99f9eab628a1896e0