Malicious PDF — malware analysis report

Static analysis result for SHA-256 6631a739252b57c3…

MALICIOUS

PDF

85.8 KB Created: 2021-06-26 05:32:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: fb29428f00c6dd99f9a1cfa647bcdd25 SHA-1: 25af1a9a69e0d44457bd958f5faa3c1eaa33fe8a SHA-256: 6631a739252b57c3a415228e6c6577fa9598f212c6df9ece52133f2be07d6546
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous URLs pointing to compromised WordPress sites, likely serving as a lure for phishing or to distribute further malware. No scripts were extracted, and the document body was unreadable, but the heuristic firings strongly suggest a malicious link distribution pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9765

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://wecafephuket.com/wp-content/plugins/super-forms/uploads/php/files/7jees3rbt4dipdv2ajggofknae/25007960338.pdf In PDF document text
    • https://lostsoulsmemorialnj.org/wp-content/plugins/super-forms/uploads/php/files/d37617a1c8281cf9b810471e88b5d36b/51334140349.pdfIn PDF document text
    • http://www.jcca.co.in/wp-content/plugins/formcraft/file-upload/server/content/files/160816d1aebe1c---61099892119.pdfIn PDF document text
    • http://kystop.com/wp-content/plugins/super-forms/uploads/php/files/gb64uc90jsi9uoe938u7ac4ll0/togegoxekawidolexem.pdfIn PDF document text
    • http://perfekttorun.pl/pliki/9657709964.pdfIn PDF document text
    • http://www.predoisiasociatii.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160b5b803444f4---10092344790.pdfIn PDF document text
    • http://www.sevenchurchestour.net/seven/wp-content/plugins/formcraft/file-upload/server/content/files/160a681629e96f---20791458455.pdfIn PDF document text
    • http://www.onlinetemsilci.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082893d324b1---zubafexupufupewoz.pdfIn PDF document text
    • http://jeremypourstarlight.com/clients/5/53/539822683240d2210db56c0084569a8b/File/bumovemaguguxep.pdfIn PDF document text
    • https://amenagementsoleil.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ebb0bdef86---35572070819.pdfIn PDF document text
    • https://mls.lighting/wp-content/plugins/super-forms/uploads/php/files/45adb3ccf0b471f243c29ae5d9f2a366/kubawisuligivemovi.pdfIn PDF document text
    • http://smartmedicaleg.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b12a2d2bc6e---bipokebipigake.pdfIn PDF document text
    • http://alarcon-v.com/editor_upload_image/file/80572927612.pdfIn PDF document text
    • http://www.guaitoli.eng.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a0c2e92fe04---78341768962.pdfIn PDF document text
    • https://sip7.pl/autoinstalator/sip7.online/wp-content/plugins/super-forms/uploads/php/files/b29267139937b232598676afd64e33fb/rimilediwunefasafoku.pdfIn PDF document text
    • http://www.pilonidalsinus.gen.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1607486b3d27a4---2076752653.pdfIn PDF document text
    • https://bmat.mn/uploads/ckfinder/files/64983711571.pdfIn PDF document text
    • http://saludocupacionalpso.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/1608779e27ac20---xozukego.pdfIn PDF document text
    • http://www.sg-callenberg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608fc43ccee6a---fexopepa.pdfIn PDF document text
    • https://www.davinci.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1609e0530aa064---xomaraxasi.pdfIn PDF document text
    • https://eclipsetheaters.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c311ca4ffcb---21070701698.pdfIn PDF document text
    • http://presssimayeshahr.ir/pic/file/43142982092.pdfIn PDF document text
    • https://prikolnaya.com/wp-content/plugins/super-forms/uploads/php/files/be33ca9172e73f1b3b40c1974283f41c/wededivizewarur.pdfIn PDF document text
    • http://bajcsidavidfoto.com/_user/file/vesoxixigibevexokasutovuk.pdfIn PDF document text
    • https://profbuhotchet.ru/wp-content/plugins/super-forms/uploads/php/files/649019ab80f37482db29df08771b75e1/rozivivajo.pdfIn PDF document text
    • https://efnnma.org/files/file/desewupijafiv.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=dauntless+how+to+boop+with+chain+bladesPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e46e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE46E 1700 bytes
SHA-256: 15171638d69c9281a983de8a04f8d213e5ed86d33053034f6aa0dd130c4010d8
font_01_sfnt_off0000ec86.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC86 10840 bytes
SHA-256: 5208dfbed8209d99f4c89badf71f0bd4159af2dc685c1a0c8e82010c671fcae9
font_02_sfnt_off00010559.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10559 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_03_sfnt_off00011d6b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D6B 16756 bytes
SHA-256: 8f6229809b0d693772edd07b4264f71b6f8f71e91c76af50ca737351204d3c41