Malicious PDF — malware analysis report

Static analysis result for SHA-256 df9bc5aab1c8bbf3…

MALICIOUS

PDF

87.2 KB Created: 2021-08-10 01:31:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b49033f19f222d1ea6520f9ec907af5e SHA-1: 4ecba65f7ba9f0e24e5de41b1df070c0f448b5d1 SHA-256: df9bc5aab1c8bbf349d540393b3fcb8192c5a8eb43ecf6b50d16ebad6737c0af
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Several heuristics point to the document being a link farm, with many URLs hosted on potentially compromised or disposable domains. The presence of multiple external URIs and link farm indicators suggests the primary purpose is to redirect users to malicious or phishing websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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 http://usaoxin.com/userfiles/2021-6/file/91313864125.pdf
    • https://patriot.ch/wp-content/plugins/super-forms/uploads/php/files/lvvb68sqi09vb78f7us3r2qa75/rajatavofasekowukirekoja.pdf
    • http://ylplj.com/ckfinder/userfiles/files/zonilarirubonidazox.pdf
    • https://gamepinleri.com/calisma2/files/uploads/jifenot.pdf
    • http://webinaris.training/ckfinder/userfiles/publics/files/notipave.pdf
    • http://vizit-k.net/uploads/editor/files/wukipemuzeratirezunobamod.pdf
    • https://queensflower.nl/clientfiles/62439411326.pdf
    • http://wildpflanzen-planung.de/file/ginejemitikele.pdf
    • http://ivepe-elearning.gr/assets/UserFiles/mainHome/file/24483843903.pdf
    • http://www.idenet.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607016ecb81c2---mukupile.pdf
    • https://denizlihorozu.com/resimler/files/50071341362.pdf
    • http://www.agrosystem.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1609e5b0f7ea85---bigirifomasukabaxim.pdf
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/bbjncrkdlnm8ljqh2tv0q9rs82/kofimovuperu.pdf
    • http://jnnycc.org/userfiles/file/zoriwiwuwufilorigepoduj.pdf
    • http://poltinik.ru/userfiles/file/73653301997.pdf
    • https://cal.lighting/wp-content/plugins/super-forms/uploads/php/files/2d8c411b977762b2f391bd3fdbd91361/15249749394.pdf
    • https://graffitipaintstudio.com/wp-content/plugins/super-forms/uploads/php/files/2de9707eec6b8afd7ed951580832b0c9/verekuxi.pdf
    • http://flygarfield.net/userfiles/file/51223125606.pdf
    • http://akcjonariusz.com/UserFiles/file/lubopenudusazaje.pdf
    • http://uniondeautoescuelas.com/wp-content/plugins/formcraft/file-upload/server/content/files/16109b4b78a0da---20603954546.pdf
    • http://hdurmuslar.com/images_upload/files/81156928376.pdf
    • https://china-glass-mosaic.com/userfiles/files/20210607_201322.pdf
    • https://radmangroup-ye.com/rgfiles/file/40536866699.pdf
    • https://www.beadvised.co.uk/wp-content/plugins/super-forms/uploads/php/files/56da1a4366fa1fd95c56bc276d9c8f80/23559368826.pdf
    • https://dalnoboy.com/data/filestorage/upload/files/57181874661.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=compare+and+order+fractions+decimals+and+percents+worksheets+pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e9f7.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE9F7 16792 bytes
font_01_sfnt_off00010209.bin
d85ec3c2c2a850a514765b0631dc74f5731e55354e940a89d9e7fde95ee05d6d
pdf-font-stream PDF embedded font (sfnt) at offset 0x10209 18696 bytes
font_02_sfnt_off000132c2.bin
0cd1b58ba89e429b3f658c6b113d2352865d6bf88cddf1325d990e9431ed4a4a
pdf-font-stream PDF embedded font (sfnt) at offset 0x132C2 11096 bytes