Malicious PDF — malware analysis report

Static analysis result for SHA-256 797598fb661248b6…

MALICIOUS

PDF

87.6 KB Created: 2021-09-05 13:49:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f6779b4ed87c3f05691f3ba5a6ab24d9 SHA-1: b0f6f8404f328866e4a8d8d6b2c28fb0a9fb3129 SHA-256: 797598fb661248b601b60e64618b6c7758dcec1623ee1efb3261b0e4e459e487
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF document that employs a link farm technique, hosting multiple PDF files on compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of numerous external links, including one pointing to a compromised CMS upload, suggests an attempt to redirect users to malicious content or exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

Heuristics 7

  • 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.
  • Fake invoice / payment lure low SE_INVOICE_LURE
    Document contains invoice or payment language paired with an action verb — useful context when combined with link, macro, or attachment indicators
  • 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://pilotcenter.gr/wp-content/plugins/super-forms/uploads/php/files/165bck3m6s7luoj04ndrrabf25/xanibomomed.pdf
    • https://cambodiadriverservice.com/userfiles/file/xagapofunawepirawijo.pdf
    • http://azizolace.cz/images/file/77012273645.pdf
    • https://capitalsyndic.com/userfiles/file/75636661279.pdf
    • https://natanashoes.com/kingkong/userfiles/files/251779007.pdf
    • https://brylka-kfz.de/wp-content/plugins/formcraft/file-upload/server/content/files/16100dd8d92fb6---nuxoxuxikezisagum.pdf
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/sjked8j3137t57opkdgnst0e7g/zukugunutuvixavogiwifodo.pdf
    • http://vudafrique.com/wp-content/plugins/super-forms/uploads/php/files/5b773e3b3720541b81fe1b5be2be3c75/26309569643.pdf
    • http://www.gamylai.vn/uploads/files/62196243613.pdf
    • http://sxhk365.com/uploads/file///88647723913.pdf
    • https://pluckywize.com/wp-content/plugins/formcraft/file-upload/server/content/files/160703f38be47e---55884944065.pdf
    • http://onmamtour.com/FileData/ckfinder/files/20210630_3D4DA205DD0ED649.pdf
    • https://www.truesdalepainting.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a5c3a60598---teripebimogukefujabani.pdf
    • https://www.femregenx.co.za/wp-content/plugins/super-forms/uploads/php/files/bgufi52pgl9m3q5read9p9pfuo/72687368815.pdf
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160c8d47496d60---muwewifijek.pdf
    • http://wumag.pl/userfiles/file/ruxusof.pdf
    • http://saovietgroup.com/upload/FCK/file/bebivimolelajiperumelone.pdf
    • http://mfahk.com/upload/files/16724950113.pdf
    • https://nnkcreations.com/userfiles/file/puzekefajujaluran.pdf
    • https://trichynext.com/wp-content/plugins/super-forms/uploads/php/files/91dbc87b310d303bec3f1e5aef077aeb/fukune.pdf
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/7u718kd6ka60plijhc5a2flar0/72474054465.pdf
    • https://www.chinacimctrailer.com/wp-content/plugins/super-forms/uploads/php/files/e533623e10ae318abd2c59c727a33ad8/vafababisupenoxesew.pdf
    • https://www.infratechgroep.nl/wp-content/plugins/super-forms/uploads/php/files/6109c8e931b41fe72d6dc91e0b98f47a/fanekofifonapozizigitaje.pdf
    • https://choiceenergynetwork.com/wp-content/plugins/super-forms/uploads/php/files/a247420abcbf55d991387a56a139e675/ziwulema.pdf
    • https://avis-medical.ma/wp-content/plugins/super-forms/uploads/php/files/5e8437e8bcbcff73684c8c61d0b48d78/65130347242.pdf
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f5a2ce7e7a---zesev.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=pakistani+construction+company+profile+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_off0000f17c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF17C 16792 bytes
font_01_sfnt_off0001098e.bin
c7f035e97781ad2c0138439f971ee872bead2948181334819af8df03aab55c2a
pdf-font-stream PDF embedded font (sfnt) at offset 0x1098E 17196 bytes
font_02_sfnt_off0001361e.bin
abe933bb6b981cc2e39fc2bc48a174029600beb26fa82247ba5403f2c9342c03
pdf-font-stream PDF embedded font (sfnt) at offset 0x1361E 11088 bytes