Malicious PDF — malware analysis report

Static analysis result for SHA-256 5b3da27ec071b3ae…

MALICIOUS

PDF

84.8 KB Created: 2021-06-25 21:00:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 93b1e46eabe663823763019bfdf101ab SHA-1: f08e6026649e7e15bc9c515b40d9e3bf6c5818e7 SHA-256: 5b3da27ec071b3aeca08ff6a6d580421585ce956ad3fb2f5e025e19050d72f8f
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ClamAV as a phishing trojan. It contains numerous links to external websites, many of which appear to be hosted on compromised WordPress installations or disposable domains, suggesting a link farm designed to redirect users. The ML classifier also strongly indicated maliciousness. No scripts were extracted, but the presence of multiple external links points to an attack pattern involving redirection to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://pistant.ru/uplcv?utm_term=ma+english+literature+mcqs+with+answers
    • https://www.focus.mu/wp-content/plugins/super-forms/uploads/php/files/c104681c1739623c6db1947e2f575429/39872847298.pdf
    • http://bamt.be/wp-content/plugins/formcraft/file-upload/server/content/files/160747c139a2e4---nopuparesoxotilipafejukud.pdf
    • http://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/cbbc37ea86e77b89abaede0566fe5e5b/vukiwerorelam.pdf
    • https://xn--z4qq44i.tw/upload/actfiles/72700757673.pdf
    • http://goodwill.as/userfiles/file/4809521787.pdf
    • http://acetuitioncentre.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607994b4bbc92---xajasoguzu.pdf
    • http://nadamasristorante.it/file/wikilavamu.pdf
    • http://aaexpansionjoint.com/wp-content/plugins/formcraft/file-upload/server/content/files/160983fa99e494---degegesewisuj.pdf
    • https://davebakeragency.com/wp-content/plugins/super-forms/uploads/php/files/fe4d96705c774698f90808fd3cd7c39c/61553959453.pdf
    • https://naseeha.org/wp-content/plugins/super-forms/uploads/php/files/306a1da8a2f3d9282d362bb617ae167e/lamojopotewopabufomazoxu.pdf
    • http://artistalexanderkanevskyroyalshakespeareglobetheatrelondon.com/clientMedia/file/86522655963.pdf
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/6ba5a0080417851f00a74edc7785fe0c/fifevimimuladimegutigodom.pdf
    • https://razdolle.by/wp-content/plugins/super-forms/uploads/php/files/o97bmfd91dlqu5sbaj7emu6o85/wilaxojuwajabonile.pdf
    • http://www.pianoszimmermann.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606d2740a7eb1---24978064123.pdf
    • http://www.uvhk.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c314b9cee76---98217127107.pdf
    • http://agiusfuneraldirectors.com/files/file/melalirasosaf.pdf
    • http://www.advancedevents.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608ff8b979b38---66398130710.pdf
    • http://www.suffaheducation.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089948f717b0---lalomezu.pdf
    • http://hongshengfish.com/uploadfiles/20210510/210510112604825216g2xg4jsjmy2e.pdf
    • https://healthmatters.me/userfiles/file/xutumabitepe.pdf
    • http://brothersaluminium.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/160c4726af2879---48855971108.pdf
    • http://westmoorclassof1965.com/clients/5/52/52ec68f2b927accf75267cb07bfcc891/File/gitebatibesuwuso.pdf
    • http://normel.org/files/upload/file/25003866778.pdf
    • http://parkwestresidences.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b4cbec2e4a1---54376511946.pdf
    • 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_off0000e734.bin
ce8895d328866aa3b6cc3400cfc8ccc1d201d5bd32b6bbae22ead88d13bc3e0e
pdf-font-stream PDF embedded font (sfnt) at offset 0xE734 16816 bytes
font_01_sfnt_off00011305.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11305 16792 bytes
font_02_sfnt_off00012b1c.bin
d8110625ab6ca82bf4ce5ae42b71874be8ce9857f270227e6f8f6144eb04eefa
pdf-font-stream PDF embedded font (sfnt) at offset 0x12B1C 10884 bytes