Malicious PDF — malware analysis report

Static analysis result for SHA-256 57aac856b88e5d33…

MALICIOUS

PDF

82.3 KB Created: 2021-07-05 21:54:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e744630135958b890970fbce184a34b8 SHA-1: b7261f121345e280a1540fcb70efc6908d7667a2 SHA-256: 57aac856b88e5d338bb57b20bbf4c092c52bb2d52408fa141cd6dcaa98673c64
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs pointing to compromised CMS upload directories, indicating a link farm strategy. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further payloads. Although no scripts were directly extracted, the PDF structure and URL patterns are consistent with malicious document delivery mechanisms.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

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 http://www.morenoroofing.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b747f24402e---89603221410.pdf
    • http://thietbixanh.net/uploads/files/59188936507.pdf
    • https://rockyshairsalon.com/wp-content/plugins/super-forms/uploads/php/files/0ro043i2qocd5469b704c0nv8j/67143952108.pdf
    • https://hmv.ir/wp-content/plugins/formcraft/file-upload/server/content/files/160b446d06aead---15039865167.pdf
    • https://bindazzled.com.au/wp-content/plugins/super-forms/uploads/php/files/d9caf09417af28a4f4145f93fea555ad/jigasekinofovakatepijived.pdf
    • http://raylutickenterprises.com/userfiles/files/tiputevanujo.pdf
    • https://forex-robo.org/wp-content/plugins/super-forms/uploads/php/files/ad7887a06b4d816e507bd0d48f5b65ac/selataponeful.pdf
    • https://hyosungulf.com/uploads/file/46272638592.pdf
    • http://bogelaipigeon.com/upload/file/29416328890.pdf
    • https://aashianarealty.com/file/21999802155.pdf
    • https://www.rekalibracija.com/wp-content/plugins/super-forms/uploads/php/files/cd6f2de9df8f5e91bdb15a7f1b49834e/22343709538.pdf
    • https://x-software.cz/data/file/fepimezima.pdf
    • https://fuchscars.com/wp-content/plugins/super-forms/uploads/php/files/383ed6327f47cf0667490ffa233526e1/46180584344.pdf
    • http://dgjst.com/upfile/file/26671687937.pdf
    • https://www.nobleorthodontic.com/wp-content/plugins/super-forms/uploads/php/files/e18ff5145371c6deb599901058173605/2022601307.pdf
    • http://sam-global.info/files/file/nogabada.pdf
    • http://automsystem.com/UploadFile/file/20210503203402621.pdf
    • http://aydinservis.com/ckfinder/userfiles/files/89878831736.pdf
    • http://www.barankayalar.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160b7b8ada6d18---nubifisabokaxitoja.pdf
    • https://www.sblending.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160798970f2081---vodefudefufex.pdf
    • http://apisicul.com/userfiles/files/lokolodeben.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=margaritas+to+go+new+braunfels
    • 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_off0000deb0.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDEB0 16792 bytes
font_01_sfnt_off0000f6c7.bin
6953dbd3997f3940975aa77e0d175b01b04b8e729ec06a2efb8db2cbd4f434ef
pdf-font-stream PDF embedded font (sfnt) at offset 0xF6C7 10708 bytes
font_02_sfnt_off00010f8c.bin
12147f8cea785c7f6bacfacb70b6461ff078a25a7ae7fb5540ccf15c671c7fc4
pdf-font-stream PDF embedded font (sfnt) at offset 0x10F8C 17088 bytes