Malicious PDF — malware analysis report

Static analysis result for SHA-256 356f8b0657d6c632…

MALICIOUS

PDF

86.9 KB Created: 2021-06-27 10:58:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 2a456715be104e0fb4cb2ca62ad5b810 SHA-1: def3d64552e8e5a79abdd131fc8a54aec5cbf34c SHA-256: 356f8b0657d6c63251b34a673dc412d6034fda7c6d456ec4d70a1b18c896bf21
156 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs that point to compromised WordPress sites, indicating a link farm or phishing lure. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to redirect users to malicious content or phishing pages. No scripts were extracted, and the document body was unreadable, but the heuristic firings and URL analysis are sufficient to determine the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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.birdandwildlifeteam.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090dd086f93b---webonamam.pdf In PDF document text
    • https://www.rockandroll.blog.br/wp-content/plugins/super-forms/uploads/php/files/u2bsohvu046cv0lj36s50quhaa/38869921152.pdfIn PDF document text
    • https://alphacleanwashing.com/wp-content/plugins/super-forms/uploads/php/files/4dd791bbe25b05b23ca50f15c550e2ff/98808500949.pdfIn PDF document text
    • http://www.absolutecateringla.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c0e8e1f7fe---98085747680.pdfIn PDF document text
    • https://alfa-pechati.ru/wp-content/plugins/super-forms/uploads/php/files/d4638ca8be84bfc16e8faf6778b513bc/45966632765.pdfIn PDF document text
    • http://www.itbaloch.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb602b5158---66066030503.pdfIn PDF document text
    • http://viaterrestre.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160ae887239142---duvudalimiterubaga.pdfIn PDF document text
    • https://markzone.az/wp-content/plugins/super-forms/uploads/php/files/9mmthridu9rsg8elaejd63sbco/22419233377.pdfIn PDF document text
    • http://objetivovender.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070732adb53d---xeberinoposajafim.pdfIn PDF document text
    • https://www.gs-gleichmann.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ba67256dd7f---9110340307.pdfIn PDF document text
    • http://mail-ex.net/userfiles/file/57752976573.pdfIn PDF document text
    • https://wacee.net/wp-content/plugins/formcraft/file-upload/server/content/files/16098fa1223885---53250251799.pdfIn PDF document text
    • https://swimproject.eu/wp-content/plugins/super-forms/uploads/php/files/844937c345e62c0656d53ad234b25efc/gomipagivutonetu.pdfIn PDF document text
    • http://srividyaastrology.com/userfiles/file/xoxolumoj.pdfIn PDF document text
    • http://smartmedicaleg.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ffc0a5789f---10077805918.pdfIn PDF document text
    • https://sitebyside.ru/wp-content/plugins/super-forms/uploads/php/files/ad130d5b41be1f893f3f0ba11bf8dfa6/nadakivobulelafupego.pdfIn PDF document text
    • http://optikametuje.cz/userfiles/file/zakulivonupirajivemelazat.pdfIn PDF document text
    • https://thehamptonsbloomington.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608387b5348fa---bipedodopiwulere.pdfIn PDF document text
    • https://shrmivirtual.org/wp-content/plugins/super-forms/uploads/php/files/183bc57626b76a927479ecc8b4f57739/nozebenubeg.pdfIn PDF document text
    • https://www.masismarketing.com/wp-content/plugins/super-forms/uploads/php/files/4311b7ee1cc2b21a1dddb8445cdd7eaa/80906764199.pdfIn PDF document text
    • https://dalyanestate.com/userfiles/file/66244703024.pdfIn PDF document text
    • https://intelean.com/wp-content/plugins/formcraft/file-upload/server/content/files/160940d750eb90---lusunil.pdfIn PDF document text
    • http://tcsm62.org/uploads/news/file/fuvuxunurin.pdfIn PDF document text
    • https://dipinkrishna.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b12c7d281de---32925646152.pdfIn PDF document text
    • https://readxyz.org/wp-content/plugins/super-forms/uploads/php/files/8e90cdd64922751ec9678cb52f48c485/kemirazibi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=1948+ford+shop+manualPDF 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_off0000ee41.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE41 10952 bytes
SHA-256: b21532f2688ce7dc0f5e12cb3e8629028f8fc060dfd7e5108d392417d9dd35bb
font_01_sfnt_off00010780.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10780 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011f92.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F92 17736 bytes
SHA-256: fdcacff5720021bddbb51a84de73f45db9ca24731be4e139a9a296f5c3abed13