Malicious PDF — malware analysis report

Static analysis result for SHA-256 2f77e103e5d5a672…

MALICIOUS

PDF

79.1 KB Created: 2021-09-06 18:50:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 830180c07ab1d8e88bb558ce52ab7b68 SHA-1: b5fa85795852b67e8f61f863b2282571434267a7 SHA-256: 2f77e103e5d5a672d75ce7143f1084796304495acf1716debcc7c65e81a6ccf7
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. It contains numerous embedded URLs, many of which point to compromised CMS upload storage, suggesting a link farm designed to redirect users to malicious sites. The document body is heavily obfuscated and unreadable, providing no direct content clues.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://higher-reason.com/wp-content/plugins/super-forms/uploads/php/files/tst39df1c6s9862i8jimbb5beu/jiwivinele.pdf In PDF document text
    • http://www.x454.com/wp-content/plugins/super-forms/uploads/php/files/966d4g85c4ovasf6ubns6rjlo2/39683484907.pdfIn PDF document text
    • http://yugang360.com/upload_fck/file/2021-8-29/20210829040018266218.pdfIn PDF document text
    • https://inchiriereelicoptere.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16085c39eb2288---denuv.pdfIn PDF document text
    • http://datev.hu/ckfinder/userfiles/files/davatemudojedaxotagizive.pdfIn PDF document text
    • https://ballestermultiservicios.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609be342838ea---kasigajipinedepisadoli.pdfIn PDF document text
    • http://vegasoft.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160a338be76e47---16234193119.pdfIn PDF document text
    • https://nikoljski.com/ckfinder/userfiles/files/33638471883.pdfIn PDF document text
    • http://winso.tw/userfiles/file/vesosinekekuxotodivi.pdfIn PDF document text
    • https://foreningenflex.se/anvandarbilder/173/files/38233957265.pdfIn PDF document text
    • https://pfgmm.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160864e07e3932---laboxaparibise.pdfIn PDF document text
    • https://vizzzio.ru/wp-content/plugins/super-forms/uploads/php/files/e38f50eb33eef3c3a69f9c06e401f57f/26174125770.pdfIn PDF document text
    • https://2greenchicks.com/wp-content/plugins/super-forms/uploads/php/files/bb5aa622f95536f86d68c1377430bb21/62203076222.pdfIn PDF document text
    • https://www.duffylighting.com/wp-content/plugins/super-forms/uploads/php/files/6d13c0c95fd3e97d5d2e022c9cf74362/libobureg.pdfIn PDF document text
    • https://xn----9sbccjdbca7cyaieg1a3j.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/bae853b73830199b33a5f026e6727c98/77529350043.pdfIn PDF document text
    • http://skyrybupaslaugos.lt/uploads/files/filudokezip.pdfIn PDF document text
    • https://altaamir.ipixpms.com/Rapport/public/assets/ckfinder/userfiles/files/51850801640.pdfIn PDF document text
    • http://sirmamedia.com/ckfinder/userfiles/files/41515634534.pdfIn PDF document text
    • https://lakeshoresmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/qn4v473iccrhp1v0iaqm5l3122/22159955927.pdfIn PDF document text
    • https://thriveelearning.com/wp-content/plugins/super-forms/uploads/php/files/5cc7675580d11d5b0939968b0a809919/lutamaxupegure.pdfIn PDF document text
    • http://kapelski.pl/userfiles/file/18007559089.pdfIn PDF document text
    • https://www.smartfutureexpo.com/ckfinder/userfiles/files/81321596753.pdfIn PDF document text
    • http://camptagola.com/clients/66689/File/rovopanimiwadigixifow.pdfIn PDF document text
    • http://dh-cell.net/ckfinder/userfiles/files/71920839891.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=el+nuevo+cerebro+humano+pdfPDF 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_off0000cff1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFF1 17560 bytes
SHA-256: 299e66d42ee5cc449752d624fd76f6b3418a38d9c3df6da8d6c57b4c2ce7ae92
font_01_sfnt_off0000fc31.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC31 10816 bytes
SHA-256: 70f63f47a83fe95e3646907678737304b11a766b7b70e435336e86ef3312ee7a
font_02_sfnt_off000114b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114B0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1