Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf4af2e81605db93…

MALICIOUS

PDF

90.2 KB Created: 2021-07-02 16:56:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8433c6181b85c79e2a88298445131e3c SHA-1: 94a8492f7f1fdac62a5c4ab70405428e005a50ac SHA-256: cf4af2e81605db93c9a33379f8b9a5e7ee916f9f4acd3ef07eb4fd4287a1858b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm on disposable hosting, with multiple URLs pointing to compromised CMS uploads, suggesting a phishing or malware distribution scheme. Although no scripts were explicitly extracted, the PDF structure and embedded URLs strongly suggest an attempt to redirect users to malicious sites, likely for further exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 https://www.hotel-palladium.gr/wp-content/plugins/super-forms/uploads/php/files/6n2c8u92jakhbdgisa2l4eh8pe/95468266623.pdf
    • https://loan-financial.com/wp-content/plugins/super-forms/uploads/php/files/31c1af5a6281aff6517fafe0d5006cc0/kidigirizav.pdf
    • http://healthywithhart.com/res/file/36864762276.pdf
    • https://acgroupenterprise.com/userfiles/file/pekidigokuzemo.pdf
    • https://extremetour74.ru/wp-content/plugins/super-forms/uploads/php/files/78b67845da93547e14a241b7441be3a1/wokeleveviruk.pdf
    • https://askopenko.com/wp-content/plugins/super-forms/uploads/php/files/223bf4e19385db342858c513f8233881/49212822052.pdf
    • http://bright-mineral.com/uploadfile/file/2021062300474078.pdf
    • https://nhaban24h.com.vn/wp-content/plugins/super-forms/uploads/php/files/4lgkq1t5cnimcbvn3ujsej89nh/63280452860.pdf
    • http://turagent007.ru/userfiles/file/50776647723.pdf
    • http://zjpjxt.cn/upload/uploadfile/file/23881295804.pdf
    • http://gf-location.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1606f2ce874c10---41949403128.pdf
    • https://hsegroup.ru/wp-content/plugins/super-forms/uploads/php/files/itfk2t09714an4fh2ncspacee3/32342809061.pdf
    • https://endoaccessories.com/wp-content/plugins/super-forms/uploads/php/files/rlvngjlktgram1gj9a1c07kp96/lomiri.pdf
    • http://shqinze.net/admin/upimg/file///37652438781.pdf
    • https://tlproduct.com/userfiles/file/rarisuwuvufifoto.pdf
    • https://westcoastmovers.ca/wp-content/plugins/super-forms/uploads/php/files/5rsq4chjhmp1tr688n8esm551v/pubavez.pdf
    • https://zanhotel.ro/beficientconsultingFiles/file/boxagugivibimup.pdf
    • http://lifemartrealestateconnect.com/wp-content/plugins/super-forms/uploads/php/files/1ki1tn5otn0hpuvcp2kfhh2mb7/41347024954.pdf
    • http://vekosgroup.ru/userfiles/file/dipimor.pdf
    • http://kfnmdg.com/upfolder/e/files/20210610155927.pdf
    • https://www.accidentinjurylascruces.com/wp-content/plugins/super-forms/uploads/php/files/7p6lgejvltjq1o016k3v0btnui/23319307882.pdf
    • http://xperion.hu/wp-content/plugins/super-forms/uploads/php/files/4b9442cc4a49ff2762e4d7e27e5035f4/kuzivafinevunuzulugatix.pdf
    • https://drmarlenebothma.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16070a03beb83d---89277819723.pdf
    • https://www.unicodesystems.com/wp-content/plugins/super-forms/uploads/php/files/u04g2bd7g2g6rv2gqkcon155h2/bamarim.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=7th+cpc+revised+pay+matrix
    • 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_off0000fc26.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFC26 16792 bytes
font_01_sfnt_off00011438.bin
8b1990ecb6af7bf5337a65370705e516cfc74c9b7c1efb308424a474ddcbd2d2
pdf-font-stream PDF embedded font (sfnt) at offset 0x11438 17248 bytes
font_02_sfnt_off00014121.bin
b261581af5af15c1734f2f5dc37e71bf34b38b42dbd1336ca146aa2fd71fdd05
pdf-font-stream PDF embedded font (sfnt) at offset 0x14121 10744 bytes