Malicious PDF — malware analysis report

Static analysis result for SHA-256 71872885a6aca17c…

MALICIOUS

PDF

85.4 KB Created: 2021-09-03 02:48:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 1d0bb6c26333d48cbc1e2318f3bd3376 SHA-1: f8cca4e1855ba4404430ecfe80adc98c26a87c7a SHA-256: 71872885a6aca17c247f3940a30926b4c3595707e722ce0f1d4d28f2e07a5305
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with many URLs pointing to potentially compromised CMS upload directories. These links likely serve to obscure the ultimate destination and distribute the payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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 http://vitanova-cattery.com/upload/file/negabofovuxit.pdf In PDF document text
    • https://mosoptagro.ru/wp-content/plugins/super-forms/uploads/php/files/9e9cc44e6a1a6f5fa91ebafa269d5104/27955215641.pdfIn PDF document text
    • http://zawayakw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0e23de6c59---vesijotufufisumope.pdfIn PDF document text
    • http://www.gaviprintpack.com/wp-content/plugins/formcraft/file-upload/server/content/files/160710f633ebd5---xifiti.pdfIn PDF document text
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/p3vvui6gilbh6ija32rvs0q0vf/92707964082.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c0c5c3d8a8d---zigimoragaripovobije.pdfIn PDF document text
    • https://takiminsahada.com/wp-content/plugins/super-forms/uploads/php/files/km96gtfj4lvgb3pdbv6beqe3ft/48362372030.pdfIn PDF document text
    • https://gaseg.com/wp-content/plugins/super-forms/uploads/php/files/s2b2il3s7oav7hu7dr7439vclt/kinefedomadojujesanira.pdfIn PDF document text
    • http://lumieretvie.com/userfiles/file/fivekusapanibumewomorer.pdfIn PDF document text
    • https://feriaesotericadeatocha.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b04bf3ac79---tomapoxumujijujixukixub.pdfIn PDF document text
    • http://adice-area.com/pictures/files/43596382294.pdfIn PDF document text
    • http://bethtikvahevents.ca/clients/2/20/20a91c0cb94b02964b0d1c5d980f1596/File/bowovim.pdfIn PDF document text
    • http://mognational.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab8d7a9fa7e---ferutejalofumavuwukukogez.pdfIn PDF document text
    • https://medok18.ru/wp-content/plugins/super-forms/uploads/php/files/fac7f37175843f196db7b08aa1c4690d/sejowerodotixudixefitamax.pdfIn PDF document text
    • https://ijfbacknumber.com/editor_up/10998909313.pdfIn PDF document text
    • https://prana.video/wp-content/plugins/super-forms/uploads/php/files/ei2mt2ece8kuao944qib2kc7rh/zazurexosavonefisudipe.pdfIn PDF document text
    • https://thejinglelab.com/wp-content/plugins/super-forms/uploads/php/files/blmktrsjb5s5si7g219asn5nr4/35887684885.pdfIn PDF document text
    • http://bigcool.net/webroot/img/files/48671442076.pdfIn PDF document text
    • http://udelimpa.es/ckfinder/userfiles/files/mobegikezafimutunof.pdfIn PDF document text
    • https://californiaoptionsrealestate.com/wp-content/plugins/super-forms/uploads/php/files/53203927df93f379a21edc61b16bd607/jakozid.pdfIn PDF document text
    • https://www.spoton.pet/wp-content/plugins/super-forms/uploads/php/files/3cmg96boe9rc2sakegbig814bs/7334705446.pdfIn PDF document text
    • https://il-gusto.com/images/file/50598676788.pdfIn PDF document text
    • http://patrick-vallot.com/upload/files/95612650643.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=2019+subaru+outback+limited+owners+manualPDF 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_off0000e163.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE163 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f97a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF97A 11316 bytes
SHA-256: 6d2b4204b2d95d75d3f81de2d5da359da17786d8a774301998b4deb878f415c8
font_02_sfnt_off00011434.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11434 19556 bytes
SHA-256: 8cc595f135ede095fb51a0bf0d517aa0f504b2e37a5a6af8c98f343d95844528