Malicious PDF — malware analysis report

Static analysis result for SHA-256 19c6b416cefcf2f3…

MALICIOUS

PDF

95.1 KB Created: 2021-08-20 17:02:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 81514b4f8f8aa5bdda94dcb3fd9d4db0 SHA-1: 3ab0daec080e1996c429a8a67696d113a96c35a7 SHA-256: 19c6b416cefcf2f3339019ea1a616ea9f1a4214ff5d1a1401e138a695ff027f6
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The presence of multiple external URIs and link farm heuristics confirms the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://chcial.ru/uplcv?utm_term=system+dynamics+ogata+4th+edition+solution+manual+pdf PDF link annotation
    • http://valeneighbors.com/userimages/71350477538.pdfIn PDF document text
    • https://www.baileysmilk.com/wp-content/plugins/super-forms/uploads/php/files/4de494758b54061a3066e2567d039dcf/bamexopof.pdfIn PDF document text
    • https://peterdegendt.be/file/gosusogezewakabevinatelox.pdfIn PDF document text
    • https://fairtradeportal.pl/userfiles/file/vefuguj.pdfIn PDF document text
    • https://www.cocochan.com.pk/wp-content/plugins/super-forms/uploads/php/files/6a79438e82e742bf327e8d15a79b3878/38227917248.pdfIn PDF document text
    • http://ateliergermain.net/sites/default/files/file/85192861310.pdfIn PDF document text
    • https://greenturtleproductions.com.au/wp-content/plugins/super-forms/uploads/php/files/875d2ab504a06ee96c596d78606a61ad/tafofod.pdfIn PDF document text
    • http://ccshecea.org/upload/files/38272839919.pdfIn PDF document text
    • http://gennarimaq.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b494db5c616---72187070848.pdfIn PDF document text
    • http://actionelectric.pt/www/wp-content/plugins/formcraft/file-upload/server/content/files/16072f275472bc---majogewowujukasug.pdfIn PDF document text
    • https://nasikampung.info/contents//files/fumirozupotenibaseb.pdfIn PDF document text
    • https://ladychief.com/wp-content/plugins/super-forms/uploads/php/files/c0e9436f36c9a41738c324d6c8c0825d/3126377347.pdfIn PDF document text
    • https://sakitonus.ru/wp-content/plugins/super-forms/uploads/php/files/eb12f1c7ec621d49c86b10412d13568e/47008798668.pdfIn PDF document text
    • http://wakingbeauty.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c7d8f90bca---87103788166.pdfIn PDF document text
    • https://www.lorenzofranzone.it/wp-content/plugins/super-forms/uploads/php/files/20389bc66111512a42d6a3098afdfe0a/lojexaxomeketofurumujuso.pdfIn PDF document text
    • http://www.scmphotography.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160723926f1113---86397427539.pdfIn PDF document text
    • https://fieldofgreen.com/wp-content/plugins/super-forms/uploads/php/files/ef032b0ad7b4c79741751eb35fa9054a/bilosasudado.pdfIn PDF document text
    • https://daaeportrett.no/upload/file/49816897134.pdfIn PDF document text
    • https://fo-prefectures.com/pages/files/2008592477.pdfIn PDF document text
    • https://www.sehersirin.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088f84d60879---6751386775.pdfIn PDF document text
    • http://papianiarch.it/userfiles/files/netefuzodofaxumadumuleri.pdfIn PDF document text
    • http://drinkandshrink.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a6e388cbe09---37052921422.pdfIn PDF document text
    • http://neodentpetrosino.it/userfiles/files/didexemibizibenukoxuvudo.pdfIn PDF document text
    • http://webursitet.org/Files/file/wifov.pdfIn PDF document text
    • https://aymexco.ro/ckfinder/userfiles/files/sidewazobuzomokujed.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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_007_off00012c82.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x12C82 23172 bytes
SHA-256: 4228452b8a8d68d634c42546fc79b1cf3712d13657cc9dc79144eda97435851b
font_00_sfnt_off0000e43a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE43A 17984 bytes
SHA-256: c019387f906ace9de4389a70ea62e7ac2cc1fc323e6cdec0f7a5dc61e6a08a6f
font_01_sfnt_off0001123a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1123A 11332 bytes
SHA-256: 4604e0a1e2b9d323aa1ce10be5f2675558f8f74bea2e95356f5971faac05f705
font_03_sfnt_off00015504.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15504 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1