Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8b7ec8637d75792…

MALICIOUS

PDF

95.0 KB Created: 2021-07-21 03:23:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 07e21259e7ea4f8491180af6a6328c61 SHA-1: 768c7036b377da8b3e027cc8ecb4bf66ee9b2109 SHA-256: a8b7ec8637d757926fb714c77326a0cade2e846463359551caea7c279db21bc3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a link farm with numerous URLs, several of which point to compromised WordPress upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. No scripts were extracted, but the structure and URL analysis suggest the PDF's purpose is to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9820

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://cottonweb.net/userfiles/file/18767541930.pdf In PDF document text
    • http://dermalab.pl/userfiles/file/67519149116.pdfIn PDF document text
    • http://marcobernini.it/userfiles/files/xitagifisuzizije.pdfIn PDF document text
    • http://www.jimenez-casquet.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ca6686a209---15111260993.pdfIn PDF document text
    • https://1877painters.com/FCKeditor/file/mutobopisegulo.pdfIn PDF document text
    • https://shrmivirtual.org/wp-content/plugins/super-forms/uploads/php/files/3f3f610fb7e0a36bbbe464f6085f61b6/3336925424.pdfIn PDF document text
    • http://amtusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080130f39550---67490518012.pdfIn PDF document text
    • http://color-gateway.com/userfiles/file/30901549910.pdfIn PDF document text
    • http://www.lentilles-progressives.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1608caa4df31a0---22731391243.pdfIn PDF document text
    • http://amphorabeautyclub.com/campannas/file/94193280527.pdfIn PDF document text
    • https://aliencosmicexpo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bca797a888a---geguxebezuxetedu.pdfIn PDF document text
    • https://bibliothequeanglaise.org/upload/files/54072246780.pdfIn PDF document text
    • http://phuvuongcorp.com/luutru/files/38753545980.pdfIn PDF document text
    • https://twr1115.net/files/fckeditor/file/14196739895.pdfIn PDF document text
    • https://themodernla.com/wp-content/plugins/super-forms/uploads/php/files/e0bdcb999c0f91ca5e8be96cfd51ae93/14080525294.pdfIn PDF document text
    • http://korealabels.com/ckfinder/userfiles/files/53743913151.pdfIn PDF document text
    • https://brandonsmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/dkds0srgin713b8g48s5q57lp2/rirowoxudosozeniwoned.pdfIn PDF document text
    • http://webscape.co.bw/wp-content/plugins/formcraft/file-upload/server/content/files/160d8ce7896a77---wivagupesomononejufax.pdfIn PDF document text
    • https://htddienstverlening.nl/userfiles/file/60683127922.pdfIn PDF document text
    • http://edwardfmcgintypa.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/40505838190.pdfIn PDF document text
    • https://www.hungryalex.com/wp-content/plugins/super-forms/uploads/php/files/79a1a0598750de4154d9ec8ec8636d0e/rabomibixed.pdfIn PDF document text
    • http://smartcookieacademy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160abbb4b01ee7---vevugotikawemu.pdfIn PDF document text
    • http://araonline.hu/uploads/file/81840703078.pdfIn PDF document text
    • http://aite-materials.com/upfiles/file/31488733391.pdfIn PDF document text
    • http://www.chicagoalphas.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079ab5b58828---jusipixujafofu.pdfIn PDF document text
    • http://www.trimbleexpress.sk/wp-content/plugins/formcraft/file-upload/server/content/files/1606d38b96e6a6---jikewodorasijako.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=signs+of+being+hydratedPDF link annotation
    • 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000110fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110FE 17084 bytes
SHA-256: 33315c5e9abf087d3ded35e711df2f6d034c65a00a90012c8c905d2e4ed75b55
font_01_sfnt_off00013d9b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13D9B 10916 bytes
SHA-256: 70d4fab1374167bfe9a418d52042bcbb36e6df6832ed208ca76a8c6f687401f8
font_02_sfnt_off000156a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x156A2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1