Malicious PDF — malware analysis report

Static analysis result for SHA-256 dbf1f7521de540e1…

MALICIOUS

PDF

84.6 KB Created: 2021-06-29 20:43:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 125445021165073080feb095bebe8a1e SHA-1: 684d10a2a841e4eb7a5430c0b1245a4bd3b7120b SHA-256: dbf1f7521de540e1f0063b0e07eef93040bb961e891046a79d255f607c892e66
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains a link farm pointing to multiple compromised WordPress sites, suggesting an attempt to redirect users to malicious content. The presence of numerous links on disposable hosting and the use of 'utm_term' parameters indicate a phishing or scam attempt, likely disguised as a document related to employment contracts.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://laihouston.com/wp-content/plugins/super-forms/uploads/php/files/1fc3cc21ddeda00f17bc124f07a912d9/muliz.pdf In PDF document text
    • https://www.treehousecare.org/wp-content/plugins/formcraft/file-upload/server/content/files/160771a58bcc94---boradepomamajiwewa.pdfIn PDF document text
    • http://wilkinsconnection.com/clients/9/94/94ba1e7d864c5c8af3bb481f5f9f31de/File/41167660113.pdfIn PDF document text
    • https://geneolock.com/locktactyuma/userfiles/file/74902004712.pdfIn PDF document text
    • http://ipublicity.cz/data/file/279320573.pdfIn PDF document text
    • https://artbynela.com/uploads/file/54595617133.pdfIn PDF document text
    • https://bibliotheque-des-arts.ch/ckfinder/userfiles/files/48587159430.pdfIn PDF document text
    • https://www.baileysmilk.com/wp-content/plugins/super-forms/uploads/php/files/670a49687da6b6b25dc4c8e99da9786e/75742796029.pdfIn PDF document text
    • https://apoc.com.au/wp-content/plugins/super-forms/uploads/php/files/2a1db9a8bf5b8eb4a6b15ce3e25cb76c/64698071984.pdfIn PDF document text
    • http://omak1968.com/clients/71178/File/15148460535.pdfIn PDF document text
    • http://zamokugrofa.sk/admin/fckeditor/file/pobasibanizorigoj.pdfIn PDF document text
    • http://sevgineslianaokulu.com/ckfinder/core/connector/php/uploads/files/fuxexuginanojimujesaka.pdfIn PDF document text
    • https://www.marthatrotts.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16078bce9f1645---nipavawekizejofatesazer.pdfIn PDF document text
    • https://propbrains.com/wp-content/plugins/super-forms/uploads/php/files/og3hfcjhmgck4hs16vnkm701i2/18988509496.pdfIn PDF document text
    • http://pamat.ro/UserFiles/file/32809601570.pdfIn PDF document text
    • http://whatdwellswithin.com/file/59747064384.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/1609cbfb292f5f---vozefukewupebuduxavejog.pdfIn PDF document text
    • https://robertmatzuzi-massagetherapist.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a9b37d63a6d---19576797428.pdfIn PDF document text
    • http://www.insurancedirectcanada.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1607e2c7dc5a49---nisiragiw.pdfIn PDF document text
    • https://csom.cz/wp-content/plugins/super-forms/uploads/php/files/b6dfa0d0005465edbab6a41676ea7d42/74694918617.pdfIn PDF document text
    • http://www.meglobalinc.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160838458a5518---kalof.pdfIn PDF document text
    • http://gopherandsquirrelcontrol.com/admin/images/file/dibemojagepuj.pdfIn PDF document text
    • http://vishwkarmaenterprises.com/webroot/img/userfiles/files/63606951060.pdfIn PDF document text
    • http://www.segurosfacility.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608c1edfabf61---xorurafurisilo.pdfIn PDF document text
    • http://hnkingdee.cn/Files/file/202152619561.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=employment+contract+extension+letter+templatePDF 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_off0000e98f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE98F 16308 bytes
SHA-256: 2c43901cae60389f987a2bb38799d206ce6860db304c816386abb92865899bd1
font_01_sfnt_off000113da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113DA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012bf1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12BF1 10732 bytes
SHA-256: f05f3498deb71274aad539816100962d70d9900ba613e59917a967731bc9830e