Malicious PDF — malware analysis report

Static analysis result for SHA-256 fe87be0b11e86abb…

MALICIOUS

PDF

83.1 KB Created: 2021-09-18 15:13:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: e7333cf5db212e11107e60f72dbcaaba SHA-1: 70b75b0bdf1ebe6daf67905f25085d123d5aba3d SHA-256: fe87be0b11e86abbe395acb6483923db08c6e6b431927d99ca69956c3e91495f
96 Risk Score

Malware Insights

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

The PDF file contains numerous external links, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier strongly flagged this PDF as malicious. The presence of multiple PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics further supports the conclusion that this document is part of a malicious campaign, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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=augmented+reality+smartphone PDF link annotation
    • http://www.findvoters.com/userfiles/file/vobuloxesuguzorekiwujosu.pdfIn PDF document text
    • https://machnhaduong.com/images/uploads/files/panorapekewazusijuzufapet.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141107697f7f---sujalerewevatazum.pdfIn PDF document text
    • http://veronikavilla.hu/userfiles/file/39197242829.pdfIn PDF document text
    • http://thebrownbag.vn/upload/files/85615113571.pdfIn PDF document text
    • https://www.auditek.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1612fcaa602b0b---73579490956.pdfIn PDF document text
    • https://theemperorsoldclothes.co.uk/wp-content/plugins/super-forms/uploads/php/files/9hadmk0nr24upl39bpdllqcjv9/95538047195.pdfIn PDF document text
    • https://hediyelikhanem.com/calisma2/files/uploads/35351472362.pdfIn PDF document text
    • http://duet-czluchow.pl/userfiles/file/41270288222.pdfIn PDF document text
    • https://saraelv.no/wp-content/plugins/formcraft/file-upload/server/content/files/16133214b526c8---78575617495.pdfIn PDF document text
    • http://scuderieverdina.it/scuderia/userfiles/file/riratisobulimebux.pdfIn PDF document text
    • http://furkansigorta.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1613150d3beb40---39064021526.pdfIn PDF document text
    • http://yalcinsezer.com/upload/ckfinder/files/zabawamikotufumanajis.pdfIn PDF document text
    • https://clubsecurite.fr/webroot/upload/files/rewojanewododo.pdfIn PDF document text
    • http://lacasedescaraibes.fr/file/72899587756.pdfIn PDF document text
    • https://vannordenvastgoed.nl/userfiles/file/retunagatuxi.pdfIn PDF document text
    • http://www.saraviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131cd03ed730---notekela.pdfIn PDF document text
    • http://jlm-kg.com/uploads/file/86146119382.pdfIn PDF document text
    • http://kroonzuivel.nl/ckfinder/userfiles/files/60331372010.pdfIn PDF document text
    • http://newworldss.com/uploads/file/35784651962.pdfIn PDF document text
    • http://chandigarhdatarecovery.com/files/file/97256478553.pdfIn PDF document text
    • https://wronba.pl/uploads/wysiwyg/file/69183411422.pdfIn PDF document text
    • https://sportuna.be/ckfinder/userfiles/files/xipirubu.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_off0000df1b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF1B 11032 bytes
SHA-256: f227b7810be06c5c512c81c325e12796999215dae1ab7499066e84e683097b58
font_01_sfnt_off0000f864.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF864 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011076.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11076 18012 bytes
SHA-256: 3e3227092a590b2c686680353e49883e8176a459b28a818eb0b35c51dc5752da