Malicious PDF — malware analysis report

Static analysis result for SHA-256 df2286255fb0623c…

MALICIOUS

PDF

68.3 KB Created: 2021-09-27 23:48:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 90c7fa8fcc3897dd0e604c7ea124f526 SHA-1: 1f3411a3934b4ac854499e504396f9ff08b769f6 SHA-256: df2286255fb0623c6a5bf19145048ba4722bd8a7d3ae29f6bf4ef1442ddda207
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains numerous embedded URLs pointing to various domains, many of which appear to be compromised or disposable hosting. The ML classifier strongly indicated maliciousness, and the heuristics identified it as a link farm. The document body is heavily obfuscated and unreadable, suggesting it's not intended for direct user interaction but rather to facilitate the redirection to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://crewmak.ru/uplcv?utm_term=pixel+text+messages+on+computer PDF link annotation
    • http://dungcubepgiangtrinh.com/webroot/img/files/80759279850.pdfIn PDF document text
    • http://petra-koparki.pl/Upload/file/42110247262.pdfIn PDF document text
    • https://floresdeserrezuela.com/aym_image/files/rinaxulerukatesa.pdfIn PDF document text
    • http://mouaumfb.com/wp-content/plugins/formcraft/file-upload/server/content/files/161504e80a6e91---gipuravokixapem.pdfIn PDF document text
    • http://schubert-hh.de/image/file/seliwerazuwajevuwune.pdfIn PDF document text
    • https://dptech.vn/uploads/files/ropegusuweriwoneripesej.pdfIn PDF document text
    • https://www.a2zmedical.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16138b9ae49d3b---zirevomepa.pdfIn PDF document text
    • https://812423.qqtogeljackpot2.com/contents/files/80284486181.pdfIn PDF document text
    • https://www.hmgfinance.com/ckfinder/userfiles/files/purudab.pdfIn PDF document text
    • http://secretlove.ch/ckfinder/userfiles/files/79256370341.pdfIn PDF document text
    • http://salt17.com/userfiles/files/77610187254.pdfIn PDF document text
    • https://www.thaiahpa.com/flash/files/51618403197.pdfIn PDF document text
    • http://www.hotel-margherita.com/wp-content/plugins/formcraft/file-upload/server/content/files/16148b7bf2f81c---vizuj.pdfIn PDF document text
    • https://skl68n15g-n2ox.com/contents/files/64973434881.pdfIn PDF document text
    • https://www.web2business.pt/wp-content/plugins/formcraft/file-upload/server/content/files/161359b5737ab3---18095505526.pdfIn PDF document text
    • http://www.alwaysflorida.com/wp-content/plugins/formcraft/file-upload/server/content/files/16151847266042---gaxasewu.pdfIn PDF document text
    • https://www.fyna.com.au/application/third_party/ckfinder/userfiles/files/pimexaded.pdfIn PDF document text
    • http://ibrahimalsada.com/pics/file/putowemuxamikimenatuba.pdfIn PDF document text
    • http://absolutelyneon.com/userfiles/file/94197517298.pdfIn PDF document text
    • https://dursunguney.com/userfiles/files/benurowa.pdfIn PDF document text
    • http://clerus.hu/files/file/raliwefagimubavixetiwexa.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_off0000ac68.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAC68 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c47a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC47A 15184 bytes
SHA-256: 9f375402804ba9985d336cc14d7eef5a2d455ade5ddd412cdb3922cfe9cc4fd6
font_02_sfnt_off0000eae3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAE3 10920 bytes
SHA-256: b36545144bf61f6a0581c0af5c509843d97dde64c5f8b8c738b7477f82913b8f