Malicious PDF — malware analysis report

Static analysis result for SHA-256 58d8b036d5ee5f5e…

MALICIOUS

PDF

85.1 KB Created: 2021-07-02 02:38:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6d843b8807dc80f06b1d04b7a8d3e346 SHA-1: f83dd798374b8706a4feea48895303d57bd34cb2 SHA-256: 58d8b036d5ee5f5ef80754e3bd5514cfd3339a04450cb8b68c209aeb9dec5663
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF document containing a link farm pointing to multiple compromised websites, many of which are WordPress installations hosting PDF files. The presence of ClamAV detection and ML classification as malicious, along with the structure of the PDF suggesting a lure, indicates a phishing or malware distribution attempt. No scripts were extracted, but the embedded URLs are the primary indicators of compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://allytemp.ru/uplcv?utm_term=previous+year+question+paper+group+1
    • https://www.sblending.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160db51503cc86---22713022046.pdf
    • http://argentum.com/wp-content/plugins/super-forms/uploads/php/files/hlpivkqljpjsgpq9r41hof5hgb/45527747118.pdf
    • https://realestateconnect.us/wp-content/plugins/super-forms/uploads/php/files/k7uo6epufg7fii7amovem21nu2/17203542471.pdf
    • https://formapolis.it/wp-content/plugins/super-forms/uploads/php/files/590cf761c5ff471829386f61ad900e26/25851197367.pdf
    • https://fobiy.net/wp-content/plugins/super-forms/uploads/php/files/d8594482f5f4f1631772d8b6a7a8d0fa/99287172234.pdf
    • http://drironcat.com/images/file/67974082685.pdf
    • https://law.com.sg/wp-content/plugins/super-forms/uploads/php/files/6e58aeb78088a7f64976b5069e7af30a/xexuragipibap.pdf
    • https://naseeha.org/wp-content/plugins/super-forms/uploads/php/files/3c3a34c8351c47695ddfb00c3da91cec/55137570402.pdf
    • https://ecobox.eng.br/wp-content/plugins/super-forms/uploads/php/files/p23dvr53m996n90n7r43be315t/84749042569.pdf
    • https://wacee.net/wp-content/plugins/formcraft/file-upload/server/content/files/160b4371d4f1ee---fusebavomi.pdf
    • http://alvasari.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608470f024818---giwekanowogumitadigizumi.pdf
    • https://carlojans.com/cms/file/silikuxorolonofefanoso.pdf
    • https://www.chartsunlimited.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/1608384abf2438---farov.pdf
    • http://www.ddd-iasi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1607f07027a636---28276389332.pdf
    • http://3handseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606e459ca3ff0---xoratumilok.pdf
    • https://globalazeri.az/wp-content/plugins/super-forms/uploads/php/files/cv25elu0gntm3n0d41alld6870/5324625004.pdf
    • https://ajur.rest/uploads/userfiles/file/29521694885.pdf
    • http://www.mediacomriccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/16083486cccaf4---18452599058.pdf
    • https://dedywiredja.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c60592b583---jepisudowajuru.pdf
    • https://www.gml.de/wp-content/plugins/formcraft/file-upload/server/content/files/16075c8be171bc---rewugidetolaripugitamev.pdf
    • http://1960whs.com/clients/7/73/73384dfd0d582a2861cf356c55c3c578/File/wutetetizinutogonifeko.pdf
    • http://chicagohalo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a555224ee2---rilapojaxabib.pdf
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/5g482b72t1p8tdeas4serbbrj3/26091533013.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_off0000ea75.bin
84b3a66385a29dc3874b870b6fa490f2327cd330f295fab0468817be6aaeba6c
pdf-font-stream PDF embedded font (sfnt) at offset 0xEA75 10860 bytes
font_01_sfnt_off0001037e.bin
66b161afc2fbd7904dd64dbd774edcd14123c69de4dba35c9a1f523e69f5b5f2
pdf-font-stream PDF embedded font (sfnt) at offset 0x1037E 16724 bytes
font_02_sfnt_off00012f1f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12F1F 16792 bytes